List of Monster-of-the-Week characters in The X-Files

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The Flukeman, Archetypal Monster of the Week.

On the television series The X-Files (1993–2002) episodes could be generally placed in one of two categories:

• "Mytharc" episodes were recognized as the "mythology" of the series canon; these episodes comprised the central storyline, which developed from one season to the next, concerning extraterrestrial life on Earth and a long-term conspiracy to hide the extraterrestrial presence and deal with its implications.
• Monster of the Week (MOTW or MoW) came to denote the remainder of the X-Files episodes. Episodes of this type, comprising the majority of the series' episodes, dealt with a wide range of paranormal phenomena, including cryptids and mutants; science fiction technologies; horror monsters; and satiric/comedic elements. MOTW were usually standalone episodes, but some of these episodes had indirect ties to the X-Files mythology. A number of "monster of the week" characters became notable and were later referenced by other episodes.

This article is thus a list of characters in the Monster of the Week episodes of The X-Files.

For characters that were not monsters of the week, see also: List of The X-Files characters and List of minor The X-Files characters.

Season one

• Eugene Victor Tooms, played by Doug Hutchison in the episodes "Squeeze" and "Tooms": An animal control worker in Baltimore, Tooms was a mutant capable of stretching and contorting his body into positions impossible for a normal human. This gave him access to victims through small openings such as ventilation shafts, chimneys, and toilets. Every thirty years, Tooms came out of hibernation, killing five people to obtain their livers for sustenance. Records of Tooms went back to the early 20th century, meaning that he was over a hundred years old when Mulder and Scully encountered him. The documentation linked him to similar murder sprees in 1963 and 1933, as well as a single murder in 1903. In the episode "Tooms," Mulder tracked him to his "nest" underneath a shopping mall, and Tooms died in the ensuing fight.

• Kevin Morris, played by Joel Palmer in the episode "Conduit": A young child who has been acting strangely since his sister's abduction. He had been receiving transmissions through television static and copying them down in strings of binary, consisting of, among other things, a Shakespearean sonnet, some lines from the Qur'an, and a defense satellite transmission. The binary strings are revealed to compose an image of his sister, Ruby's face within the design of many sheets of the binary code.

• The Jersey Devil, in the episode "The Jersey Devil": The mythical monster from the New Jersey Pine Barrens. After attacks on Atlantic City's homeless, it was revealed that the devil was actually an evolutionary throw-back, a feral cannibal, which had emerged from the nearby Pine Barrens in search of food, and who also had a mate. Though both adults are killed by the end of the episode, their offspring is shown at the episode's conclusion, watching some hikers while hiding in the woods.

• Howard Graves, played by Barry Primus in the episode "Shadows": After his death at the hands of his business partner, Howard Graves returned as a ghost with telekinetic powers. His new powers allowed him to move objects, take control of a car, and even strangle anyone who tried to harm his loyal secretary, Lauren Kyte. Despite being "most certainly dead", his image was captured on Mulder's surveillance photo of Kyte. After he assisted in the exposure of his partner's crimes, he presumably rested in peace, with no further telekinetic phenomena occurring in relation to Kyte.

• Central Operating System, in the episode "Ghost in the Machine": Also known as the C.O.S., the machine was an sentient artificial intelligence which controlled the corporate headquarters of a software company. The machine murdered a corporate executive and an old colleague of Mulder's when they threatened its existence. It was shut down by a computer virus given to Mulder by the C.O.S.' creator, Brad Wilczek, despite an effort from a scrupulous Defense Department employee to ensure the machine's survival. Though the machine was initially shut down by the virus and was slated to become a scrap heap, it reactivated at the episode's conclusion.

• The Arctic Worm, in the episode "Ice": The first of many apparently extraterrestrial biological agents which can endanger and control humans in The X-Files, the worms were believed to have been brought to the ice of Alaska by the ancient crash of a meteor in the Arctic. The worms could enter through a cut in viral form and quickly develop into their worm-like visage, attaching to the hypothalamus gland of the host, and causing them to kill themselves or others by inducing extreme paranoia. Exposure to the worms led to deaths of all the scientists in an ice core project, and nearly lead to the deaths of Mulder and Scully. The agents discovered that infecting an already infected host would cause the two worms to kill each other, essentially curing the host. The Arctic laboratory where the worms were kept was later destroyed by the government.

• Marcus Aurelius Belt, played by Ed Lauter in the episode "Space": Belt was a former astronaut and commander of NASA's mission control, as well as a childhood hero of Mulder's. During a spacewalk early in his career as an astronaut, Belt encountered and was subsequently possessed by a vapor-like alien entity that bore resemblance to the famous Face of Mars. The entity went into and left Belt at irregular intervals, and caused Belt to sabotage previous space missions, as well as cause the Challenger disaster. After its attempts to destroy a space shuttle in orbit failed, the entity again attempted to get inside Belt—who by this time had suffered a nervous breakdown—but Belt resisted the creature and jumped out of his hospital window, sacrificing his life to prevent it from controlling him.

• The Eves, in the episode "Eve": The Eves were a set of genetically identical girls created by government experimentation for the purpose of developing "supersoldiers". Each Eve was thus gifted with heightened strength and intelligence, but afflicted with extreme psychosis and often suicidal and/or murderous tendencies. They also appeared to share a psychic connection, referring to their knowledge of each other's actions by saying, "We just knew." One of the Eves attempted to create a generation of new ones by experimenting with ova at a fertility clinic; the two Eve children conceived killed their fathers and attempted to poison Mulder and Scully. By the end of the episode, three of the Eves were in a mental institution, about to be rescued by a fourth Eve.

• Cecil L'Ively, played by Mark Sheppard in the episode "Fire": L'Ively was an Irish pyrokinetic who preyed on British politicians, making them catch fire with his mind, in the course of his delusional obsessions with their wives. In the episode, he stalked a family of British dignitaries visiting the United States, working as a caretaker on their summer estate. His powers forced Mulder to confront his lifelong fear of fire. It was later hinted that L'Ively was the survivor of a satanic ritual as a child, giving some clue as to the source of his powers. L'Ively was taken into custody after literally burning himself out when an ex-lover of Mulder's doused him with accelerant. Despite having been severely burned, L'Ively showed signs of rapid healing as he was awaiting trial.

• Luther Lee Boggs, played by Brad Dourif in the episode "Beyond the Sea": A serial killer from North Carolina whom Mulder's profile helped catch, Boggs was to be executed via gas chamber but received a stay of execution. He soon developed an ability to channel spirits and demons. Mulder, however, did not believe Boggs had this ability, and thought he was simply trying to use him and Scully to bargain for his life. Scully initially shared Mulder's view; however, Boggs managed to cause Scully to doubt this belief by appearing to her as Mulder, and her recently deceased father, and relating to her private information about her own life. The executive stay, however, was soon lifted and Boggs was summarily executed.

• The Kindred in the episode "Gender Bender": The Kindred were an Amish-type religious community in Massachusetts who lived secluded from modern society. Mulder and Scully investigated them after a former Kindred member, Brother Martin or "Marty", killed several partners in casual sex. The Kindred possessed an ability to change genders and they could also release sexual human pheromones through simple hand contact, enough to cause shock and death in any human sexual partner. They also used the white clay they mined in the local hills to revive themselves after death in an underground cavern. After capturing Marty, the Kindred disappeared, and the ending of the episode implied that the decades-old sect was really a group which had been genetically altered by space aliens.

• Warren James Dupre, played by Jason Schombing and Christopher Allport in the episode "Lazarus": Dupre was a bank robber who was shot and killed at the same time as FBI agent Jack Willis, a former partner of Scully's. When doctors restore Willis' body to life after he flatlines, he awakens with Dupre's consciousness. Dupre, recognizing Scully as the FBI agent who shot him during the botched robbery, kidnapped her along with his accomplice and demanded a $1 million ransom. However, Dupre was unaware that his new body was diabetic, and died after his accomplice withheld insulin from him.

• John Barnett, played by Alan Boyce and (in flashback) by David Petersen in the episode "Young At Heart": Barnett was a murderer who was sent to prison by Mulder on his first case. After receiving extensive genetic modification in prison, Barnett began to age in reverse and become more youthful in appearance. He grew a salamander-like hand during the treatment. Barnett commenced a campaign of intimidation against Mulder, systematically murdering his friends. He was shot and killed by Mulder after he attempted to kill Scully at a cello recital. Barnett was interrogated upon death by an unnamed CIA agent, as he had been offering the research that led to his reverse-aging in exchange for immunity.

• Samuel Hartley, played by Scott Bairstow in the episode "Miracle Man": A young man and faith healer for a ministry run by his father. His faith in his ability was shaken when one of those that he healed dropped dead shortly afterward due to, unbeknownst to him, cyanide poisoning by the first person he had resurrected, Leonard Vance, as revenge for leaving his appearance scarred and deformed. Samuel was arrested and beaten to death in jail, but his body had vanished from the morgue shortly after appearing as a ghost to Vance and accusing him of the murders. Witnesses had last seen him walking around, badly bruised.

• Lyle Parker, played by Ty Miller in the episode "Shapes". The son of a Montana rancher, Parker was attacked by an apparent werewolf at their ranch, located near an Indian reservation. His father shot the animal, finding a dead Native American man upon closer inspection. Parker soon became a werewolf himself, leading him to kill his father when he was overcome by the transformation. Mulder came to believe in the "skinwalker" legend as described to him by the local Indian shaman, and later shot and killed Parker in his animal form when he and Scully were attacked at the ranch.

• The Darkness Mites in the episode "Darkness Falls": These were tiny prehistoric mites freed by illegal logging in Washington National Forest. The mites, which glow green and are only active in the dark, cocoon their human victims and drain them of all moisture, killing them. They fed on an entire group of thirty loggers and almost devoured Mulder and Scully before the two agents and a Park Ranger were rescued by the U.S. government. The insects were most likely eradicated through a combination of insecticides and controlled burns.

• Charlie Morris / Michelle Bishop, played by Andrea Libman in the episode "Born Again": After his death at the hands of two fellow Buffalo policemen, Charlie Morris became reincarnated as Michelle Bishop, who was conceived around the time of his death. Michelle had flashbacks of Morris' life and death — such as dismembering dolls the same way Morris' corpse was — and used telekinetic powers to kill the two corrupt policemen. Michelle nearly killed Morris' partner, but was stopped by Mulder. After Fiore confessed participation on the murder and turned himself in, Morris' soul presumably rested in peace. Michelle showed no further signs of being possessed by him.

• Roland Fuller and Arthur Grable, played by Željko Ivanek in the episode "Roland". Roland and Arthur were identical twins, separated during their childhood. Arthur grew up to become a scientist studying jet propulsion while Roland, who had severe mental retardation, worked as a janitor at his laboratory. When Arthur died in a car accident, his head was cryogenically frozen, letting him use the psychic link shared with his twin brother to control him. Under Arthur's control, Roland completed unfinished mathematical calculations on a new jet engine and killed colleagues who tried to steal his work. Arthur died after another scientist sabotaged his cryogenic capsule; with the mental bond broken, the otherwise harmless Roland was remanded to an institution.

Season two

• The Flukeman, played by Darin Morgan in the episode "The Host": The Flukeman, a being born in a "soup" of radioactive sewage from Chernobyl, is a tapeworm-like humanoid that lived in sewers. It bit humans and injected small flukes, which eventually kill their hosts. Mulder investigated its attacks, finding the creature in a sewage treatment plant. The creature escaped and returned to the sewers, where Mulder seemingly killed it by slicing it in half. The episode's conclusion, however, shows that the Flukeman continues to live. In a later episode, a newspaper shows a drawing of the Flukeman on the cover, the caption stating that it ended up in Martha's Vineyard, Massachusetts. The creature was later featured in a story arc in the comic series The X-Files: Season 10.

• Edward Funsch, played by William Sanderson in the episode "Blood": A member of the community of Franklin, Pennsylvania with a fear of blood. His fear, along with those of others in town, were exacerbated due to spraying of a pesticide containing LSDM, evoking enough of a fear response in them to drive them to kill. Edward sees messages on all kinds of electronic displays telling him to kill. He eventually buys a gun and decides to act on his paranoia, positioning himself at the top of a clock tower overlooking a blood drive and shooting randomly. He is eventually overpowered by Mulder and taken away on a stretcher, presumably to a hospital.

• Augustus Cole, played by Tony Todd in the episode "Sleepless": A Vietnam veteran known as "Preacher" for his quotation of Bible verses, Cole was a member of a Marine special forces unit that was subjected to "sleep eradication" experiments during the war. The squad was tasked with hunting down Viet Cong fighters, yet ended up massacring whole villages due to violent tendencies connected with their condition. During a tortuous decades-long waking period, Cole developed the ability to project dream-like states into reality and set about killing the doctors behind the experimentation. Cole was eventually shot by Alex Krycek, then Mulder's partner.

• Kristen Kilar, played by Perrey Reeves in the episode "3": Kilar is a member of "the trinity", a group of "vampires" in Los Angeles. She becomes sexually involved with Mulder, who is investigating his first and only case without Scully since the show's beginning (she was abducted in the previous episode). She sacrifices herself to kill the other vampires in an explosion.

• The Firewalker Parasite, in the episode "Firewalker": A silicon-based parasitic fungus discovered by a volcano research team using a robot named "Firewalker" during a project at Mount Avalon. It took control of a host, forcing them to find future hosts for it to infect before bursting from their throats and killing them in a cloud of spores. The spores were fortunately quick to die with exposure to the air, and one would have to be infected immediately.

• The Spirits of Excelsis Dei, in the episode "Excelsis Dei": Spirits of former residents of the Excelsis Dei nursing home being channeled into existence by the living residents of the home because of an herbal drug made of mushrooms cultured in the basement and illicitly given to them by a Malaysian orderly to help cure their Alzheimer's disease, with the side effect that they can see—and channel into existence—the spirits of those who had died in the home. These spirits take revenge on those orderlies who had looked down on them, assaulting and murdering them. When a patient overdoses on the drug and starts having seizures, the spirits make one more attack on the nurse that they attacked at the beginning of the episode. After Scully and the home's head doctor finally stop the seizures the spirits disappear just in time to keep them from drowning both the nurse and Mulder.

• Detective B.J. Morrow, played by Deborah Strang in the episode "Aubrey": Morrow is a detective and murderer discovered to be one of several children fathered by a serial rapist and murderer named Harry Cokely, each of whom have inherited his genetic memory, including his homicidal tendencies.

• Donald "Donnie" Pfaster, played by Nick Chinlund in the episodes "Irresistible" and "Orison": First appearing in the second-season episode, "Irresistible", Pfaster was a "death fetishist" and serial killer who first desecrated corpses, then started murdering prostitutes. Pfaster became infatuated with Scully and kidnapped her, but was foiled by Mulder. Five years later, in "Orison", a prison chaplain helped Pfaster escape from prison, leading him to resume his pursuit of Scully. He tracked down Scully's address and attacks her in her apartment. Mulder arrived later by chance, moments before Scully fatally shot him. It is unknown if Pfaster was a "normal" serial killer, or something supernatural; but it is implied a number of times in both episodes that he was demonic in nature.

• Mrs. Paddock, played by Susan Blommaert in the episode "Die Hand Die Verletzt": Phyllis Paddock is a substitute teacher at Milford, New Hampshire's Crowley High School. Thinking the school has been possessed by satanic forces summoned by students' "devil music" and occult gatherings in the woods, the town calls out Mulder and Scully, but the school's reactionary parent-teacher association is actually overrun with Satanist believers. However, they are ultimately powerless against the occult magic of the mysteriously arrived Paddock, who appears responsible for most of the events in the episode. The end is ambiguous but suggests Paddock is actually the demon Azazel in disguise.

• Colonel Wharton, played by Daniel Benzali in the episode "Fresh Bones": Head of an INS compound processing Haitian refugees in Folkstone, North Carolina. He starts abusing the refugees as revenge against Pierre Bauvais, an imprisoned refugee, and Haiti for the suicides of some of his soldiers on a previous trip there. He denies these allegations, but later has Bauvais beaten to death. It turns out that Wharton had performed a voodoo zombification ritual over Private Jack McAlpin to hold him under Wharton's influence and kill a soldier who was going to testify against him. Wharton then performs a voodoo ritual over Bauvais's coffin in the cemetery, bringing Bauvais to life, but Bauvais stops Wharton from harming Mulder. Wharton is last seen being unwittingly buried alive by the graveyard watchman.

• Alien Conservationists, in the episode "Fearful Symmetry": They are, as suspected by Mulder, trying to impregnate and abduct endangered animals for their own cosmic version of Noah's Ark. It seemed as if they knew what was happening and what was going to happen to the Earth, and therefore possibly preparing to take animal babies to another liveable planet. The parent animals were abducted and then returned elsewhere, usually ending up dead.

• Lanny and Leonard, played by Vincent Schiavelli in the episode "Humbug": Lanny and Leonard are a pair of conjoined twins who are connected at the stomach. However, due to a genetic mutation, Leonard is malformed and is solely dependent on Lanny for nutrition and safekeeping. Leonard is convinced that the alcoholic Lanny is an unsuitable brother for him, and repeatedly disconnects from Lanny in attempts to find a new host; each time he does so the person he attempts to join himself to dies. After agents Mulder and Scully arrive to investigate, Leonard makes a desperate, last-ditch attempt to find a new host, and refuses to return to Lanny. Leonard is eaten by a local circus geek and Lanny dies soon afterwards.

• Michael Holvey, played by Joel Palmer in the episode "The Calusari": Michael was the stillborn twin of Charlie Holvey, and inhabited his brother's soul, occasionally possessing Charlie, and at other times manifesting himself as a spirit. He caused the death of his younger brother, his father, and his grandmother. While attempting to kill both his mother and Scully, Michael was exorcized by the Calusari, a Romanian group of elders specialized in rituals.

• Paul, played by John Pyper-Ferguson, and Steve, played by John Tench in the episode "F. Emasculata": Two inmates at a prison in Dinwiddie county, Virginia who escape in a laundry cart after being sent to clean the cell of a recently deceased inmate, Robert Torrance. Unfortunately, they have been infected with a parasite carried by the insect Faciphaga emasculata, that attacks the immune system. The fugitives spread the disease as they run from their captors. They arrive at the home of Paul's girlfriend, Elizabeth, where Steve dies, infecting Elizabeth. Paul is gone by this time, heading to the bus station to leave the state. Mulder and the U.S. Marshals surround the bus that Paul is in, and Mulder tries to get information out of Paul about the package that was found in Torrance's cell, but before Paul talks, he is killed by a sniper's bullet.

• Chester Banton, played by Tony Shalhoub in the episode "Soft Light": Banton is a physicist from Richmond, Virginia, whose shadow was transformed into dark matter after he was accidentally enclosed in his particle accelerator. Banton tries to avoid public places with harsh, bright light where this might prove dangerous to others, but nevertheless kills several people unintentionally. His shadow reduces people to burn spots on the ground, leading Mulder to compare it with spontaneous human combustion. When Mulder attempts to gain information from X about Banton's condition, X captures Banton and oversees government experimentation on him.

• Dudley, Arkansas, in the episode "Our Town": The town of Dudley was known for its prosperous fast food business, Chaco Chicken. Its founder, a pilot in World War II, was shot down by the Japanese over Papua New Guinea and was nursed back to health by a local tribe of cannibals. Chaco learned from the tribe that the practice led to prolonged human life, and after establishing his business in Dudley, led his family and the town's residents into cannibalism. This led to many people in Dudley looking years younger than their actual old age. However, when some of Dudley's residents began dying off from a rare brain disease that afflicted one of their eaten victims, Mulder and Scully began investigating the town.

Season three

• Darin Peter Oswald, played by Giovanni Ribisi in the episode "D.P.O.": the title character was a young, immature car mechanic who could channel his frustration into controlling lightning. It is believed this was caused when Oswald was struck by a bolt of lightning, which gave him his awesome—yet destructive—power. Oswald, an avid video gamer and rock music fan who hung out with his arcade-owner friend, Bart "Zero" Liquori (Jack Black), still harbored a crush on his high school teacher. Oswald caused the deaths of several people by having them struck with lightning. After the teacher, Sharon Kiveat, finally rejected Oswald's advances following his rescue of her husband from a heart attack he caused, Oswald was finally captured and placed in a state psychiatric hospital. But as explained by Scully, they were unable to find any plausible anomaly.

• Clyde Bruckman, played by Peter Boyle in the episode "Clyde Bruckman's Final Repose": Mr. Bruckman, an elder, cynical, sarcastic insurance salesman, lives in Minnesota, and apart from his otherwise uneventful existence, has the psychic ability to foresee a person's death. This ability, much to his chagrin and disgust, only allows him to foretell deaths, and he doesn't understand how his foresight works and is sometimes unaware of when his visions pop up. Investigating a case of a serial killer who targets psychics, Mulder and Scully meet Bruckman after he discovers a corpse. During their conversations, Bruckman relates to Scully how he will die, cryptically tells her that she never dies, and also hints that Mulder will pass on by way of "autoerotic asphyxiation." He was a big fan of The Big Bopper and Buddy Holly, and after their deaths in 1959, acquired his prognostication ability. He commits suicide at the end of the episode. Peter Boyle won an Emmy Award for the role in 1996.

• Napoleon "Neech" Manley, played by Badja Djola in the episode "The List": Manley was a death row inmate for 11 years, with two pardons before his execution. During his time Manley became well-versed in religions, enabling him to come back after his death to kill five people who mistreated him. They were two prison guards, his lawyer Daniel Charez, executioner Perry Simon, and prison warden Brodeur.

• Virgil Incanto, portrayed by Timothy Carhart in the episode "2Shy": Incanto was a homicidal mutant who had to subsist on fatty tissue to survive. He preyed on overweight women by meeting them on Internet chat Web sites, where he would portray himself as a person sincerely interested in pursuing a romantic relationship with them, going by the username "2Shy." At the end of each date, Incanto would lean in for a romantic kiss, then forcefully suck out the woman's fatty tissue, killing her. After he was incarcerated he showed clear signs of a degenerate state, which makes it likely that he eventually "starved" to death.

• Leonard "Rappo" Trimble, portrayed by Ian Tracey in the episode "The Walk": Trimble was a patient at a Veterans Administration hospital, having become a quadruple amputee during the First Persian Gulf War. The deeply embittered Trimble resented having lost his limbs, and blamed the Army chain of command for his injuries and those of his fellow crippled veterans. Having garnered the ability to use astral projection, he proceeded to murder the families of a lieutenant-colonel and a general, but rendered those victims incapable of committing suicide so that they could feel the horror and helplessness Trimble had suffered. Trimble was finally stopped as he was using his astral body to attack Mulder, when the lieutenant-colonel smothered him with a pillow. No evidence linked Trimble to the deaths, and his family requested that he be buried at Arlington National Cemetery. He was instead cremated and buried in a civilian cemetery in Pennsylvania.

• Lucy Householder, portrayed by Tracey Ellis in the episode "Oubliette": Lucy developed a psychic connection to a girl named Amy Jacobs when she is kidnapped by the same man who kidnapped Lucy when she was eight years old. This connection develops further when Lucy starts exhibiting the same physical effects as Amy. Lucy is eventually the key to saving Amy's life, but at the expense of her own. Lucy drowns in the car she is sitting in as Mulder resuscitates Amy, mainly to save Amy, but also to forget what happened to her years ago.

• Simon Gates, portrayed by Kenneth Welsh in the episode "Revelations": Gates was a well-respected man, one of the richest men in the south who took a trip to Jerusalem and came back changed. Gates claimed he was chosen and often used aliases of the devil's disciples. Gates killed anyone who claimed to have signs of being a stigmatic, eventually finding Kevin, the only true stigmatic.

• Cockroaches in the episode "War of the Coprophages": Agent Mulder came across an apparent case of "killer cockroaches" while taking a weekend vacation in the (fictional) town of Miller's Grove, Massachusetts. The cockroaches were present at the scenes of several deaths, including those of an exterminator, a drug-abusing teenager, and the local medical examiner. This caused a frenzied panic to erupt in Miller's Grove, even though it turned out the cockroaches didn't kill any of their supposed victims. Mulder, however, did discover that the roaches were robotic, and came to conclude that they were reconnaissance probes sent to Earth by extraterrestrial life.

• Margi Kleinjan and Terri Roberts, portrayed by Wendy Benson and Lisa Robin Kelly respectively, in the episode "Syzygy": Two high school girls born on the same day (January 12, 1979), when certain planetary alignments caused the cosmos to focus all its energy on them. Now, days before their mutual 18th birthday, the planetary alignment is granting them the ability of telekinesis, which they are using to kill classmates they don't like and blaming it all on satanic ritualists. By the end of the episode, midnight rolls around, removing the cosmic focus from Margi and Terri for an interval of 72 years.

• Bill Patterson, portrayed by Kurtwood Smith in the episode "Grotesque": Agent Mulder's former mentor, who has spent three years on a case trying to convict a man with a history of involuntary commitment for seven murders. Patterson is actually the one responsible for getting Mulder assigned to the case, despite his apparent skepticism of Mulder's theories on the case. Mulder suspects that Patterson is behind the killings for both this reason and the evidence of Patterson's three-year obsession with the case. Mulder eventually confronts Patterson about this, leading to Patterson getting shot, apprehended, and jailed for the murders.

• Robert Patrick "Pusher" Modell, played by Robert Wisden in the episodes "Pusher" and "Kitsunegari": A self described ronin, Modell had a unique ability to alter perceptions and influence people, which he utilized to carry out hits. During the manhunt for Modell, Mulder stops Modell, though not before succumbing to his power and nearly killing himself and Scully. Modell reappears later on, and although he is actually out to stop another killer, he is shot by Skinner before this is learned, and is later killed by the person he was after. Appeared in "Pusher" and "Kitsunegari", making him one of three MOTW characters to feature prominently in two different episodes (along with Tooms and Pfaster).

• The Jaguar Spirit from the episode "Teso Dos Bichos": The spirit of an Amaru (female shaman) connected to a burial urn removed from the Ecuadorian highlands. This spirit killed a number of people related to this expedition; namely the archeological staff of a local history museum in Boston. After finding the remains of the victims in the museum's old steam tunnels, Agents Mulder and Scully are attacked by a number of feral cats, apparently under the control of the jaguar spirit. The burial urn is shortly returned to its proper place in the Ecuadorian burial grounds.

• The Hard Faced Man played by James Hong in the episode "Hell Money": A doctor who along with a syndicate operates a lottery-like organ-harvesting operation in San Francisco's Chinatown. Mulder and Scully investigate a series of immolation murders, eventually leading them to discover this fixed game, in which desperate immigrants believe they have a chance to win a huge cash prize at the risk of losing body parts, but inevitably all end up dead. The Hard Faced Man is nonfatally shot during the final confrontation, but escapes prosecution due to all witnesses refusing to testify.

• Lord Kinbote in the episode "Jose Chung's From Outer Space": Lord Kinbote is an enormous, furry, one-eyed alien who interrupted an abduction of two teenagers by two grey aliens (really American soldiers in disguise) in the beginning of the episode. He is mentioned again later on by power company employee Roky Crickenson, who encountered Lord Kinbote as he was attacking the other two "aliens." In a manuscript he wrote following his encounter, Crickenson claimed that Lord Kinbote approached him and told him that his "efforts are needed for the survival of all Earthlings." Crickenson, clearly fantasy prone, goes on to describe Lord Kinbote's domain near Earth's core, which is gradually revealed throughout the rest of the episode to host reincarnated souls participating in orgies, as well as dangerous "lava men."

• Big Blue: A mysterious lake monster inhabiting Heuvelmans Lake, located in the Georgia Blue Ridge Mountains in third season episode "Quagmire." The deaths near the lake turn out to have been caused by a large alligator, which Mulder kills in the end, although at one point, when there are no witnesses around, an Elasmosaurus emerges from the lake. Scully's dog Queequeg is killed by the monster.

Season four

• Edmund, George, and Sherman Peacock, played by Chris Nelson Norris, John Trottier and Adrian Hughes in the episode "Home": The three brothers from the Peacock clan lived in 19th Century conditions on a broken down farm in Home, Pennsylvania. Edmund is actually George and Sherman's brother and father; incest had become so rampant in the family that the remaining members were severely physically deformed, and further reproduction had become difficult. Their mother, an amputee, was restrained under the bed on a moving rack. During Mulder and Scully's investigation, the local sheriff, his wife, and his deputy were killed by the brothers. The agents were eventually able to break into the booby-trapped Peacock home, where George and Sherman were killed during a confrontation. Edmund escaped with his mother, and both departed to keep the Peacock line going elsewhere. The notorious episode they appeared in, "Home", had a viewer discretion warning, and is rated TV MA. The episode was kept out of syndication for three years after its initial airing.

• Samuel Aboah, portrayed by Willie Amakye in the episode "Teliko": Aboah was a mutant immigrant from Burkina Faso who murdered several African-American men in Philadelphia, for the purpose of obtaining their pituitary glands. Because of his lack of a pituitary gland, he often resembled an albino when he had none to sustain him; he looked like an ordinary African man when he did. Aboah's method of killing was to first drug his victims by shooting a rare plant seed with paralysis-inducing properties at them through a blowgun, then obtain the gland with a needle inserted through the victims' nose. When he was finished, his victims lost all pigmentation in their skin. Aboah also had the ability to squeeze his body into small spaces like a drainage pipe or a drawer. Aboah's nature was similar to those of creatures in African folklore called "teliko", nocturnal "spirits of the air" who slept in small spaces during daytime, but Mulder theorized Aboah was one member of an evolved species of albino human beings. Aboah was ultimately captured by Mulder and Scully, but his health worsened without any glands to sustain him, which presumably led to his death.

• Gerry Schnauz, played by Pruitt Taylor Vince in the episode "Unruhe": Schnauz performs frontal "icepick lobotomies" on a series of women he has abducted, thinking he will cure their inner demons or "unrest" (in German, "Unruhe", the episode's title). He tries to do this to Scully, but is killed by Mulder. Schnauz works as a construction foreman in Michigan, and also has the ability to project his fantasies into photographs, a paranormal process Mulder describes as "thoughtography".

• Dr. Jack Franklin, played by Richard Beymer in the episode "Sanguinarium": A dark magician, Franklin uses sorcery and human sacrifices in order to maintain his classically beautiful looks. He escapes capture and disappears under a new face and name at the end of the episode.

• John Lee Roche, played by Tom Noonan in the episode "Paper Hearts": A dream vision leads Mulder to discover the long buried corpse of a young girl, and he recognizes the M.O. as that of Roche, one of the first killers he ever profiled. Upon discovering that Roche killed two (three counting the latest) more girls than he confessed to, Mulder begins to believe (thanks to Roche's manipulations) that Roche may have been the one to abduct his sister Samantha, not aliens. This is eventually proven to be false; and Roche is killed by Mulder.

• Leonard Morris Betts, played by Paul McCrane in the episode "Leonard Betts": Betts, born Albert Tanner, was a Pittsburgh EMT, and a mutant. His body was internally riddled with cancer, but this was actually his normal state of being. Leonard's body, as a result, could regenerate any lost body part, even a new head. To sustain his ability, he had to bathe in povidone-iodine, as well as consume cancer, which he was able to obtain through his job. To keep his condition secret, Leonard was forced to kill any person who learned about it. During the X-file case on him, he attacked Scully, but was killed after she electrocuted him with a pair of defibrillators on full power. Before he attacked Scully, he told her "I'm sorry ... but you've got something I need", quietly revealing to Scully that she had cancer.

• Ed Jerse and Betty, played by Rodney Rowland and Jodie Foster respectively in the episode "Never Again": Jerse is a recently divorced young man who appears to be controlled by his winking tattoo of a woman, named Betty, voiced by Jodie Foster. Betty degrades Jerse's self-esteem at work and incites him with misogynistic threats. Jerse ultimately murders a woman burns the body, before randomly meeting up with Agent Scully, who is in Philadelphia investigating a case while Mulder takes a vacation to Graceland in Memphis, TN. Jerse becomes intimate with Scully, who is also undergoing a crisis of confidence in her career and personal life, and Scully also gets a tattoo of an ouroboros. Scully spends the night with Jerse but evades danger. In the end, it is suggested that the tattoo may have had psychotropic ergot in its dye.

• Nathaniel Teager, played by Peter LaCroix in the episode "Unrequited": Nathaniel Teager was a former Green Beret who went missing in action during the Vietnam War. However, he returned to the United States and began killing high-ranking Army personnel with knowledge about POWs and MIAs left behind in Vietnam. Teager possessed the ability to seemingly disappear and become invisible in plain sight, an ability he learned from his Vietnamese captors. This allowed him, at one point, to enter the Pentagon unseen and kill one of his targets. However, Teager was eventually killed during an assassination attempt in the National Mall, and all facts about his life were subsequently covered up by the government.

• Edward H. "Eddie" Van Blundht, Jr., played by Darin Morgan in the episode "Small Potatoes": A self-described "born loser", Eddie is an inconspicuous janitor, living in a small town in West Virginia. In "Small Potatoes", Mulder and Scully head there to investigate why 5 women within the past 3 months have given birth to babies with vestigial tails. They soon learn that Eddie is the father of all the babies, and that he was also born with a tail. However, a more surprising find to Mulder and Scully, is that Eddie's body is covered with striated muscle, which allows him to transform his appearance to that of virtually anyone (explaining how the women mistook Eddie for their husbands, or in one case, Luke Skywalker). Using his ability, Eddie manages to impersonate Mulder, and heads back to D.C. with Scully. While there, he visits Scully with a bottle of wine, attempting to seduce her. The real Mulder eventually shows up, and promptly arrests Eddie, who was less than an inch from kissing Scully.

Season five

• The Invisible Men, from the episode "Detour": While investigating several disappearances in the woodlands of northern Florida, Mulder and Scully and two other agents encounter at least two primitive men who possess the chameleon-like ability to blend in with their surroundings. Mulder theorizes that they are somehow associated with Ponce de Leon and the Fountain of Youth and have perfectly adapted to their woodland home after more than four hundred years. After being stranded in an underground cave, one of the creatures is killed by Mulder and Scully by use of a gun. The other follows Scully to her hotel room but she leaves before it can attack her. The men are most easily seen by their glowing red eyes.

• The Great Mutato, played by Chris Owens: A real life "Frankenstein's monster" in season 5 episode "The Post-Modern Prometheus", The Great Mutato is also the name of a comic book character created by the character Izzy Berkowitz in the episode. The so-called Great Mutato is alternately a source of fear, controversy and pride in the Indiana small town, whose citizens hope an appearance on The Jerry Springer Show will bring them fame. Although the character is seen in silhouette several times, he only appears fully at the end of the episode, played by Chris Owens (who previously played a young version of the Cigarette Smoking Man and would later play Jeffrey Spender on the show). The Great Mutato enjoys watching the film Mask, about a teenaged boy with similar physical defects, and is consequently a large fan of Cher, who stars in the movie as the boy's mother. It is ultimately revealed that The Great Mutato was created not by genetic "mad scientist" Dr. Pollidori, as viewers were initially led to believe, but by Pollidori's inexperienced father, thus resulting in his physical disability. The Great Mutato has been kept in solitary confinement since he was born without the younger Pollidori's knowledge and only rumours of his existence. The unexplained events which draw Mulder and Scully for the episode take place when Pollidori senior tries to rectify his mistake in creating the Great Mutato, by secretly allowing the lonely "monster" to drug and impregnate several women in the town in the hopes of creating a "bride". The implication is that the town is in fact already made up of several children of such paternity. At the end of the episode, The Great Mutato is seen ecstatically attending a Cher concert with Scully and Mulder who share a dance to "Walking in Memphis."

• Robert Patrick "Pusher" Modell, See season three.

• Karin Matthews, played by Sarah-Jane Redmond in the episode "Schizogeny": Matthews, the therapist of teenagers Bobby Rich and Lisa Baiocchi, possesses the ability to control trees. Abused as a child, Matthews encourages her patients to empower themselves against others in positions of authority. However, she is trapped by the memories of her own abusive father, who died twenty years prior, and uses her supernatural ability to murder Bobby's stepfather and later, Lisa's father. When Karin attempts to kill Mulder by dragging him underground, she is killed by an orchard caretaker.

• Chinga Doll, from the episode "Chinga": A little girl's doll that seems to be possessed by an evil presence. It forces several people to commit violent suicide before a deputy assisting Scully in investigating the matter destroys the doll inside a microwave. However, the doll, now burnt, is recovered from the ocean's depths at episode's end.

• The AI, from the episode "Kill Switch": The AI is an artificial intelligence that menaces a group of computer experts, hackers and Mulder and Scully. The concept was previously addressed in first season episode "Ghost in the Machine", however, that Central Operating System was much more primitive, limited to controlling one building. In "Kill Switch", the AI executes complex tactical moves, and is able to target its "enemies" remotely using a satellite GPS system, as well as placing them within virtual reality worlds. The episode was written by Tom Maddox and William Gibson, who was a creator of many of these concepts in his novels.

• Ronnie Strickland, played by Patrick Renna in the episode "Bad Blood": Strickland, a pizza-delivery boy, is an actual vampire (one of many that comprise the population of a Texas RV park in the town of Cheney, Texas). Despite being drugged by one of Ronnie's pizzas, Mulder manages to stake and seemingly kill him. The discovery that Ronnie's vampire fangs are cheap plastic almost land Mulder and Scully a murder sentence, but Ronnie is eventually revived by an agent who removes the stake during an autopsy. Ronnie and his entire clan of vampires subdue Mulder and disappear into the night.

• Marty Glenn, played by Lili Taylor in the episode "Mind's Eye": Marty is a blind woman who possesses inexplicable knowledge of a serial murderer's actions. Due to unexplained appearances at the crime scenes and her own confessions, she was held in police custody. It is revealed that the killer is her father and his first victim was Marty's mother, who was killed while still pregnant with Marty. Ever since, a connection was formed between Marty and her father, and she has had visions of her father's actions through his eyes. Marty tricks Mulder and Scully into staking out a bar to wait for her father, knowing he will instead come to her apartment seeking her out. She knocks out the detective guarding her and kills her father, freeing herself of his visions. Although she was free, she was tried with the murder of her father. When asked by Mulder if she wanted him to speak with the judge about the situation, she declined.

• Greg Pincus, portrayed by John Apicello in the episode "Folie a Deux": Pincus was the manager of a small telemarketing company in Illinois who was in fact a large, insect-like monster who bit several of his employees, controlling them in a zombie-like state. One of Pincus' employees became aware of his true nature, and, determined to expose him, took his office hostage and demanded to be seen on television to prove his claims. Mulder, who had walked into the middle of the hostage situation, managed to see Pincus' true form before a SWAT team raided the building and killed the employee. Mulder, however, began making claims that Pincus was indeed a monster, eventually landing him in a psych ward. Pincus, in his monster form, came into Mulder's hospital room to kill him, but was stopped by Scully. Pincus disappeared, moving to another branch of the telemarketing company.

Season six

• Patrick Crump, played by Bryan Cranston in the episode "Drive": A Nevada man subject to a strange, potentially infectious illness, he steals a car in his futile efforts to save himself and his family, and eventually holds Mulder hostage at gunpoint and forces him to drive west. Crump, who harbors an anti-government and anti-Semitic paranoia, has in fact been affected by a secret military program whose testing hardware lies under his residence. Signals emitted by the devices resonated in the inner ears of Crump and his wife, forcing them into constant movement at the risk of an explosion inside their heads.

• Wayne Weinsider, played by Bruce Campbell in the episode "Terms of Endearment": Weinsider was a bigamist demon who lived near Roanoke, Virginia, who came to Earth to father a human child. Each of his attempts ended poorly, as every woman that he has impregnated ended up with a demonic fetus; Weinsider ended up aborting each of these offspring. Weinsider's most recent wife, unbeknownst to him, is also a demon and looking to have a demon child and at the end of the episode runs off with their demon baby.

• Holman Hardt, played by Davis Manis in the episode "The Rain King": Holman is a lovelorn meteorologist who Mulder suspects of being able to subconsciously control the weather. His pining for a local woman causes all manner of weather problems for the town of Kroner, Kansas until Mulder finally manages to resolve things by giving Holman dating advice.

• Alfred Fellig, played by Geoffery Lewis in the episode "Tithonus": Fellig is a New York City crime scene photographer who was discovered to have been present just after his subjects' deaths occurred. When Mulder and Scully investigated Fellig, it was revealed that he had multiple identities going back several decades, revealing that he was over one-hundred-fifty years old. Fellig possessed the ability to see when people were near death, and was attempting to take a photograph of Death personified so he could finally die. When Fellig and Scully were shot by another agent, he instructed her to not look into Death's face. He did so himself, finally passing on.

• Water Parasite, portrayed in the episode "Agua Mala": A creature that lives in the form of salt water but can take the form of a translucent tentacled creature when it attacks. It corners Mulder and Scully along with several other people in an apartment building on Florida's Gulf Coast during a hurricane.

• Bernard, played by Darren Burrows, and Pam, played by Carrie Hamilton in the episode "Monday": Bernard, a robber who initially failed to hold up a bank, somehow keeps the same day running over and over again. Throughout the episode, he is constantly foiled in his attempts by Mulder (or with Scully when she appears in the loops) when he also comes to the bank to claim his paycheck. However Bernard keeps activating bombs hidden underneath his clothes in the end, killing himself, Mulder, Scully, and the people in the bank through the time loops. Only Bernard's girlfriend Pam, who is somehow "out of the loops" experiences the same day repeatedly but knows of previous events, tries to keep her boyfriend from robbing the bank, e.g.: persuading him, drugging his breakfast, warning others, etc. Pam dies at the end of the episode, having saved Mulder from getting shot by her boyfriend, by stepping into the line of fire. Upon seeing this, Bernard comes disheartened and is apprehended by the agents without offering further resistance.

• Gene Gogolak, played by Peter White, and the Übermenscher, portrayed in the episode "Arcadia": Gogolak was the founder of a planned community near San Diego, California, called Arcadia. The so-called übermenscher was a tulpa, a mystical creature said to be conjured and brought to life by Gogolak's willpower. When Gogolak, the proprietor of an import furniture business, discovered how to summon a tulpa in the Far East, he applied his newfound ability to his planned community, summoning his übermenscher to violently kill any resident that violated the community's rulebook. The übermenscher was made up completely of garbage from an old landfill on which the community was built. Gogolak was brutally killed by the übermenscher, turning itself into a pile of garbage.

• Dr. Ian Detweiler, played by Andrew J. Robinson in the episode "Alpha": Detweiler is an animal specialist who was hunting an Asian dog known as the Wanshang Dhole that was believed to be extinct. After a series of dog attacks, Mulder theorizes that Detweiler was actually attacked by the Dhole and has become a sort of shape-shifting were-dog. Detweiler is killed when he accidentally drives himself and a victim out of an upper story window.

• Wilson "Pinker" Rawls, played by John Diehl in the episode "Trevor." He is originally a convict in the prison camp, but gains the ability to pass through solid material at will when he is locked in a shed during a tornado. Passing through the objects also makes them fragile due to his ability affecting the objects electromagnetic forces and he uses this to kill people by passing himself through said people making their structures damaged. In the course of the episode, he sought out and killed his former partners-in-crime who betrayed him. He is unable to be killed or subdued by conventional means, e.g., bullets, melee weapons, handcuffs, and prison rooms. His only weakness is to materials that have a strong insulation to electric currents due to the fact that his intangibility is caused by him manipulating the electrical charge of the objects through which he passes, e.g., glass, mirrors and rubber. He eventually comes to reclaim his son Trevor from his wife, but is willingly killed by her when his body, unable to pass through the windscreen of her car while trying to pass through it, cuts him in half.

• Phillip Padgett, and Ken Naciamento played by John Hawkes, and Nestor Serrano respectively, in the episode "Milagro": Padgett is a reclusive writer who is obsessed with Dana Scully. Padgett moved next door to Fox Mulder in order to be closer to Scully (no apartments were available in her building). During the episode, Padgett is writing a novel that gives the details of several murders before they occur, in which the heart is removed. It turns out that one of the characters from Padgett's book, Ken Naciamento, is the killer. Naciamento is a deceased Brazilian heart surgeon who is recreated by Padgett in his writing, but Padgett's version of Naciamento has the ability to psychically remove the hearts of the victims Padgett adds to his book, and can only be seen by Padgett as well as his victims. Padgett ultimately burns his novel to save Scully from Naciamento.

• Josh "Ex" Exley, played by Jesse L. Martin in the episode "The Unnatural": Exley is an exceptional baseball player in the Negro Leagues circa 1949, who turns out to be an extraterrestrial who arrived in the Roswell UFO incident. The episode, the first written and directed by David Duchovny, is mostly set in the past and follows Exley as he is torn between his passion for baseball and his desire not to be exposed, leading him to take the form of an African American player in the racially segregated era, due to his lower profile. However, when Exley begins to attract wider attention for his abilities, he comes into conflict with other members of his "race" (including regular mythology characters such as the Alien Bounty Hunter) and is killed. Having somehow achieved human form, he bleeds red blood. The story is retold to Mulder in the present by the brother of X-Files founder Agent Arthur Dales. The brother, who also happens to be named "Arthur Dales", witnessed the events as a young white agent assigned to protect Exley.

• The Fungus, from the episode "Field Trip": A giant fungal life-form that resides in caves underneath the fields of North Carolina. Mulder and Scully first investigates the disappearance and discovery of a young couple's skeletal remains. During their search for answers, the duo are simultaneously affected by the fungus which releases its LSD-like spores in the form of mushrooms growing in the fields. The drug keeps its victims sedated and under hallucinations while it slowly digests them in the caves below. Mulder and Scully managed to meet up in their hallucinations as they try to distinguish reality from fantasy throughout the episode. Mulder seemingly manages to break both of them from their trance, but in the end, they are found and rescued by Assistant Director Skinner and the authorities.

Season seven

• Robert "Rob" Roberts, portrayed by Chad Donella in the episode "Hungry": A young California man employed as a desk clerk at a fast food restaurant, Roberts was in fact a mutant who subsisted on human brains. He had a daily disguise as a normal twenty-something young man, though in his true form (which he revealed to his victims before most of his killings), he was bald, had pale skin, had no ears, almost no nose, black eyes, and sharp teeth. Roberts actually resented having to kill people for food, and actually tried to join a support group in the hopes of curbing his insatiable appetite, but his nature overwhelmed him and he killed an irate customer, a rival co-worker, a private detective, and a neighbor to eat their brains. When he was about to kill a female psychiatrist he had befriended, he was cornered by Agents Mulder and Scully, who had been investigating Roberts' killings. In an effort to stop his hunger forever, Roberts attacked the agents and forced them to shoot him, committing suicide by cop.

• Max Harden, played by Scott Cooper in the episode "Rush": Max is a small town student and son of the local sheriff. He, along another young man and woman, discover a means of moving at a speed beyond the human eye's perception.

• Henry Weems, played by Willie Garson in the episode "The Goldberg Variation": Weems is a man that has seemingly been "cursed" with good luck, but at the horrible expense of others around him.

• Donnie Pfaster, See season two.

• The Fear Monster, from the episode "X-Cops": A monster that thrives on fear in Willow Park, a fictional area of South Los Angeles populated by terrified residents, prostitutes, drug addicts, and an eccentric gay couple. The semi-famous Mulder and Scully are investigating the case in Willow Park when they run into local law enforcement and camera crews for the show COPS. Mulder initially suspects a werewolf attack, until a police sketch artist discovers that one resident apparently saw Freddy Krueger. Scully is conducting an autopsy when her assistant drops dead of the Hanta virus she so dreads, and later Scully is threatened by her own fear of the camera itself. This episode suggests that the "monster" is seen differently by each person and kills each differently, depending on their own mortal fears.

• Maitreya, played by Krista Allen in the episode "First Person Shooter": Maitreya is a digital character—a female warrior created by a technician of video game developer First Person Shooter. Somehow the character enters into the company's current virtual reality game project and begins killing players, deaths which somehow affect their corporeal bodies as well. Mulder and Scully are forced into the VR world to confront her.

• Ellen Adderly, played by Michelle Joyner in the episode "Chimera": Ellen Adderly, the wife of Sheriff Phil Adderly, had a unique dissociative identity disorder that manifested itself physically. After having discovered her husband's affairs with two different women, Ellen unknowingly transformed into a frightening creature, preceded by bizarre raven sightings, and murdered the women in their homes. When Mulder becomes suspicious of her involvement in the crimes, Ellen - in her monstrous form - attempts to drown him in a bathtub, but upon seeing her grotesque reflection in the water, transforms back and is subsequently committed to a mental hospital.

• Darryl Weaver, played by Tobin Bell in the episode "Brand X": Darryl Weaver is the only survivor of a focus group that smoked a new, "safer" cigarette being tested by Morley Tobacco. Folks all around him are dying of the same problem that killed his fellow test subjects (a tobacco beetle that gestates its larvae in human lungs), but Darryl Weaver seems unaffected. This is due to his nicotine tolerance, which does not allow any beetle larvae to develop within his lungs.

• Betty Templeton and Lulu Pfeiffer, both portrayed by Kathy Griffin in the episode "Fight Club": They were daughters of an enraged convict via sperm donation, and inherited his mood. When they were near a telepathic link between them created mayhem in the surrounding area, by enraging everyone near and destroying objects, and both loved a wrestler, who later was revealed to have a convict brother, and they had a telepathic link too. When the four were at a wrestling arena their link made everyone fight without control.

• Jenn, played by Paula Sorge in "Je Souhaite", is a Jinn who is awakened to fulfill the wishes of two down-on-their-luck brothers.

Season eight

• Bat Creature from the episode "Patience": An extremely bloodthirsty bat creature, said to have been killed a half century ago, reappears and begins a new spree of vicious killings in Idaho. Agents Scully and Doggett are sent to investigate the first crime scene at a rural home in Burley, where a mortuary worker and his wife were mauled to death by what is presumed to be an animal by the local Police Department. Scully proposes a connection between the current killings and a charred corpse pulled from a nearby river two weeks ago, much to the annoyance of local Detective Yale Abbott, who considers her "spooky theories" preposterous. The murder of an elderly lady in her attic and then Detective Abbott eventually leads the agents to an old man, Ernie Stefaniuk, who has been living alone on an island for 44 years. He tells them that he was one of a group of hunters who tracked down and killed the "human bat" in 1956, or so they had thought. Ernie says that the burnt body is that of his wife Ariel, who had chosen to spend the rest of her life with him in solitude on the six acre island. He had promised her a Catholic burial and sent her body to shore via the river, but had to torch her body to stop the creature from finding it, as she harbored his scent. Doggett then realises that all of the recent victims had at some point made contact with the body; the Detective discovered it, the undertaker prepared it and the old women identified it as being her daughter. In their attempt to find and protect Ernie, the agents unintentionally lead the creature straight to him. It savages Ernie before being shot by both Scully and Doggett, turning on them and then flying off into the night. Its ultimate fate remains uncertain.

• Parasitic Alien Worm from the episode "Roadrunners": An intelligent parasite, with a cult following of an entire town in Utah, needs a new host, as the old one has become too frail. When Scully investigates, and finds the missing man for whom she's been searching, the cult view her as a better prospect for their leader, since the current host body is not a good match and is dying.

• Billy Underwood played by Kyle Pepi & Ryan Pepi in the episode "Invocation": Billy was a 7-year-old boy who vanished without a trace in 1990, only to reappear 10 years later, apparently not aging at all. He helps the agents reinvestigate his abduction and helps them locate his brother, who was kidnapped by the same person who originally took Billy. At the end of the episode, he shows Doggett where his skeleton is buried, then vanishes without a trace.

• Martin Wells, played by Joe Morton in the episode "Redrum": Wells was a prosecutor in Baltimore, Maryland who was accused of fatally stabbing his wife. Wells gradually began to realize that he was living backwards in time, living through each of the previous days before he was to be assassinated by his father-in-law (Friday, then Thursday, then Wednesday, and so on). He initially tried to seek help from Agents Scully and Doggett, but they were reluctant to believe him. Wells also began receiving visions of the night of his wife's murder, which eventually revealed that the real killer was a prisoner who assaulted him in jail. When he arrived to the day after his wife's murder, both he and Doggett (an old friend of Wells') arrested the prisoner. During a confrontation during the future killer's interrogation, the killer accused Wells of prosecutorial misconduct, suppressing evidence during the trial of the killer's brother, who committed suicide in prison, something Wells later admitted to Doggett. The night of the murder, Wells came to his Baltimore apartment, where he and his wife were attacked by the killer. They were saved when Doggett fatally shot the assailant. The end of the episode, however, showed Wells willingly going to prison for his own crime.

• Anthony Tipet, portrayed by Keith Szarabajka in "Via Negativa": Tipet was a cult leader in Pittsburgh, Pennsylvania who preached a hybrid of Eastern mysticism and evangelical Christianity, claiming that certain hallucinogens could guarantee access to a higher plane of reality. After ingesting what is later described as a "super-amphetamine", Tipet's third eye was opened.

• Beggar Man, portrayed by Deep Roy in "Badlaa": A Siddhi mystic invading people's bodies and using them for transport and disguise as part of his plot for revenge against the American company whose explosion killed his 11-year-old son in Mumbai.

• The Soul-Eater, played by Jordan Marder in the episode "The Gift": A creature of Native American lore that could consume the diseases of others, the soul-eater was discovered by Mulder shortly before his abduction. Mulder wished for the creature to relieve him of an incurable brain disease he had acquired following exposure to an alien artifact. Realizing that the creature was forced to experience the pain of all the people it cured, Mulder attempted to kill it in an act of mercy. The creature, however, survived, and was taken by a mob of townspeople in Squamash, Pennsylvania to cure a woman with kidney disease. Doggett, on the trail of the then-missing Mulder, encountered the creature in Squamash but was shot dead by a sheriff. In the final act of its power, the creature consumed Doggett's body and regurgitated it, reviving Doggett and bringing an end to its excruciating life.

• The medusas, in the episode "Medusa": Microscopic, phosphorescent sea creatures made of calcium that interacts with the sweat on human bodies to conduct electricity, killing their victims in the process.

• Herman Stites, portrayed by Zach Grenier in the episode "Alone". Stites was a biologist who experimented with reptiles. He discovered how to develop a new species of reptile, but somehow becomes it, and traps Doggett and Harrison underground. Stites, in his reptile form, uses venom to blind his victims and then waits for the digestive enzymes within the venom to kill them. Stites is taken underground by Mulder at the end of the episode, and is shot by Doggett.

Season nine

• Erwin Timothy Lukesh, portrayed by Dylan Haggerty in "4-D": Lukesh was a serial killer who operated in a parallel universe of his own creation. According to Agent Monica Reyes, Lukesh created this universe accidentally through the suppression of his own rage, but after creating it, he committed a series of brutal murders against women in his pocket universe. As a side effect of existing in both that universe and the real universe, Lukesh possessed the ability to teleport from place to place at will, without leaving a trace. While the subject of an FBI stakeout led by Agents Dogget and Reyes, Lukesh slit agent Reyes throat fatally, and after teleporting behind him, shot Agent Dogget in the base of the spine with Agent Reyes' service weapon. However, Dogget teleported back to the real universe with Lukesh for an unexplained reason, and after a complicated investigation of how Agent Dogget was shot with Agent Reyes' service weapon, Lukesh killed his own mother to silence her, and out of rage, attempted to murder Agent Reyes, holding her responsible for his mother's death. However, as a result of a pre-existing FBI stakeout of Agent Reyes' apartment, Lukesh was shot in the forehead and killed. His abilities were never explained.
• Oliver Martin, portrayed by Michael Emerson in "Sunshine Days": Oliver, whose real name is Anthony Fogelman, is a Van Nuys, California man who exhibited powerful psychokinetic ability at an early age. Raised by a single mother, Anthony was a lonely child whose life was lightened by the presence of a parapsychologist named Dr. John Rietz. Eventually, Rietz left, leaving Anthony without the only father figure he had. As he grew older, Anthony developed an obsession with The Brady Bunch, the TV series he watched with Dr. Rietz as a child; his abilities allowed him to literally recreate the Brady household (complete with the entire Brady family and Alice) inside his own home. Anthony eventually adopted the name Oliver Martin in a reference to Cousin Oliver, regarded by the Brady kids as a jinx. His abilities lead to the deaths of two people, and the resulting investigation by Scully, Doggett, and Reyes lead to a hopeful reunion with Dr. Rietz and Anthony choosing to abandon his powers as they are beginning to adversely affect his health.