The agents' first case takes them to Oregon to investigate the unsolved murders of several high-school classmates.

Mulder and Scully head to Ellens Air Force Base to investigate the mysterious case of a military test pilot who disappeared after experiencing strange psychotic behavior. While on the case, Mulder meets a mysterious man dubbed 'Deep Throat' who claims to have classified information about his investigations into the paranormal.

Mulder and Scully search for a humanoid killer whose savage murder spree reoccurs every thirty years.

As Section Chief Blevins expresses his concern with the direction of the X-Files, Mulder becomes obsessed with solving a case that closely parallels an encounter he experienced as a child: the abduction of his kid sister, Samantha.

Mulder and Scully track a legendary creature that has roamed the New Jersey countryside for over forty years.

Mulder and Scully investigate the deaths of two men believed to have been killed by a powerful psychokinetic force.

It's Halloween, and Mulder and Scully are investigating the strange death of a corporate executive in a sophisticated high-tech building.

In the claustrophobic isolation of a remote outpost in Alaska, Mulder and Scully investigate the horrifying deaths of scientists.

Mulder and Scully are contacted by a communications specialist from NASA who shows them evidence of sabotage in the space programme.

Mulder puts the future of the X-Files in jeopardy when he heads to a UFO crash site being rapidly covered up by the military. He is arrested, and while in jail he meets Max Fenig, a UFO nut whose NICAP group has followed Mulder's work on the X-Files. When Mulder is released, Scully urges him to return to Washington to face his superiors and try to save his job, but Mulder finds out that Max is more than meets the eye and ignores Scully to try and save him instead.

When two fathers on opposite sides of the country are inexplicably murdered at the exact same time in the exact same way, Mulder and Scully are called in to investigate. When they discover that the two fathers' eight-year-old daughters are identical twins, they realize that something even stranger is going on.

An old Oxford girlfriend of Mulder's asks for his help on an international case concerning the unexplainable execution of several British dignitaries, and they encounter an assassin who can produce fire from his bare hands.

When death row inmate Luther Lee Boggs claims to be psychic and can lead Mulder to a serial killer in return for a lesser sentence of life in prison, Scully becomes an unwilling believer when Boggs tells her that she can communicate through him with her recently deceased father.

A series of sexually-oriented murders, which are identical except that the killer appears to be both male and female, draws Scully and Mulder to an Amish-type community of people called the Kindred.

When FBI Agent Jack Willis and bank robber Warren Dupre are both shot at the same time during a robbery attempt, Dupre dies when Willis is brought back to life. When Willis rushes out of the hospital and begins acting strangely, Mulder concludes that Dupre has come back to life in Willis' body.

Mulder becomes the target of someone from his past named John Barnett. He was a jewelry store robber with an itchy trigger finger that Mulder sent to prison when he first joined the Bureau. The only problem is that Barnett died four years ago.

Mulder and Scully receive information from Deep Throat about a UFO that was shot down over Iraq and has been secretly transported to the US. However, Deep Throat then intentionally misleads the agents to prevent them from discovering the truth.

A young man who has the power to heal people with his touch begins to question his gift when people start dying after he has supposedly healed them.

Mulder and Scully travel to a Native American reservation to investigate the death of a man who was mistaken for a wild animal and may have been the legendary Manitou, a man who can shape-shift into a beast.

When a group of loggers in the Washington State National Forest disappear in the same way that another group disappeared 50 years ago, Mulder and Scully go along to investigate and find themselves trapped in a cabin surrounded by flesh eating insects that only attack at night.

Eugene Tooms is released from the sanitarium, and Mulder becomes personally involved to ensure that he is caught in the act of getting the last human liver he needs to go into hibernation for another 30 years.

After a detective and his former partner die in unexplained circumstances, the accidents are linked to a little girl who witnessed both deaths. Mulder believes that she may be the reincarnation of a policeman murdered by his colleagues.

Mulder and Scully investigate the death of a scientist working on advanced propulsion technology. The mentally challenged janitor Roland, who has secretly been completing the scientist's work, is the prime suspect.

When Deep Throat points out a news story about a fugitive who apparently drowned, Mulder and Scully cannot see what makes the case special but follow it up anyway. With Deep Throat's insistence, they discover evidence of a secret government project code-named Purity Control, which uses human test subjects and infects them with extraterrestrial DNA. However, the evidence and everyone who has seen it is quickly being eliminated.

With the X-Files closed, Scully has been assigned as an instructor at the FBI Academy while Mulder is doing menial surveillance work. After meeting with Senator Matheson, one of his supporters in regards to the X-Files, Mulder disobeys orders and heads to an abandoned SETI site in Puerto Rico which has inexplicably reactivated itself and could provide proof of contact with extra-terrestrial life.

A.D. Skinner sends Mulder to investigate a body which washed into the New Jersey sewer from the ocean. Mulder believes that the basic blue-collar assignment is punishment, but by Skinner's own admission, what he discovers is a true X-File.

When several violent deaths in a small farming community are connected by the destruction of digital devices, Mulder believes that people are being driven to kill by the use of subliminal messages in the digital readouts.

Mulder reluctantly accepts a new partner, Agent Alex Krycek, and they investigate the deaths of several Green Beret soldiers who participated in a sleep deprivation experiment during the Vietnam war.

Mulder is called to a hostage situation involving Duane Barry, a former FBI Agent who claims to be an alien abductee and wants to get back to the abduction site with someone who will be taken instead of him. Unfortunately, the someone he eventually chooses is Scully.

When Mulder finds out that Scully was kidnapped by Duane Barry, he risks the wrath of his superiors and the annoyance of Agent Krycek in order to do whatever it takes to find her. Meanwhile, Krycek is found to be reporting Mulder's activities to the Cigarette-Smoking Man.

Mulder, back on the X-Files but alone for the first time, investigates a series of vampire-like murders in Los Angeles and finds himself falling for the one woman that may be the prime suspect.

Scully mysteriously appears in a Washington hospital, alive but in a coma, and Mulder must fight to keep her alive in order to find out what happened to her and who did it to her. Meanwhile, Scully fights her own personal battle as she decides whether to stay or go on to the next world.

Mulder and Scully, reunited at last, head for an active volcano under a geological study and find a deadly life form that can survive in the searing heat of the crater and is killing the scientists to avoid being discovered.

While investigating the connection between the abduction of several teenagers and a rural religious cult, Mulder and Scully discover a secret test being performed on the children using the "Purity Control" alien DNA from 'The Erlenmeyer Flask' which leads Mulder to "the crew-cut man", Deep Throat's murderer.

Mulder and Scully uncover strange occurrences in an elderly care home when one of the nurses is attacked by an unseen force she claims to be one of the 90 year old residents.

When a detective mysteriously uncovers the remains of an FBI agent who disappeared in the 1940s while investigating a similar murder case to one she is now on, Mulder and Scully believe that the original killer had passed his genetic trait of violence to his grandchild.

A mortuary worker who gets his thrills from collecting hair and fingernails from the dead begins killing his soon-to-be collectibles himself and sets his seriously disturbed sights on Scully.

The ritualistic murder of a teenager in a small town gets Mulder and Scully caught up in a secret occult practice within the local school's PTA and a substitute teacher with strange powers.

While investigating several deaths and murders within a Haitian refugee camp, Mulder and Scully get caught in the middle of a secret war between the camp commander and a Voodoo priest.

After the obituaries of four identical men are e-mailed to Mulder, the agents are contacted by a shadowy CIA agent who tells them about a bounty hunter sent to wipe out the beginning of a colony of clones. Meanwhile Mulder is distracted by the sudden reappearance of his sister Samantha.

The alien bounty hunter kidnaps Scully and wants to trade her for Mulder's sister, who is revealed to be a clone herself. After the trade goes badly and Mulder discovers the truth about Samantha, he tracks the bounty hunter to his ship buried in the arctic ice and demands the whereabouts of his real sister.

In a small town in Idaho, a man is killed by what seems to be an invisible elephant. Mulder's investigation into the local zoo, its owners and a local animal rights group uncovers evidence of insidious alien experiments.

When half the crew of a Navy ship abandon their boat in a life raft and are rescued 18 hours later looking about 60 years older than they should be, Mulder suggests that the ship is caught in a time field which is speeding up their aging.

Mulder and Scully travel to Gibsonton, Florida, a town built and populated by circus and sideshow performers to investigate the death of Jerald Glazebrook, The Alligator Man. While searching for leads on the killer, the agents come across many bizarre characters including the local sheriff who was once known as Jim Jim, the Dog-Faced Boy.

The agents investigate when a young boy's family is plagued by a series of tragic accidents.

When a plague-like illness kills ten men inside a maximum security prison, Scully tries to get into the quarantine site and discover the cause and origin of the contagion, while Mulder and a group of US Marshals track two escapees who may be infected.

An experiment in dark matter accidentally turns a scientist's shadow into a deadly weapon that can unzip a person's molecules if they are touched by it.

After several disappearances in a small town, Mulder and Scully investigate and find hundreds of human bones in the river. They discover that the man behind the town's main source of wealth, a chicken processing plant, has found a way to prolong his life through cannibalism.

Mulder receives an encrypted computer disk containing the defense department's top secret files on extraterrestrial life and becomes a target. Scully takes him to a Navajo family that unearthed a buried secret to decipher the disk.

Scully finds her career with the FBI in jeopardy as Mulder is still missing and the Cigarette Smoking Man is pursuing the stolen files. The Navajo elders find Mulder's body in a cave and perform an ancient ceremony to call the spirit back to the empty vessel.

A.D. Skinner and Scully are at a standoff when Mulder bursts in and discovers that Skinner has the digital tape. Reunited, Mulder and Scully travel to a secret vault inside a mine and find an elaborate filing system of medical records which reveals that Mulder's sister may not have been the first choice for abduction. Meanwhile, Skinner deals with the Cigarette-Smoking Man for their safety.

Mulder and Scully investigate a series of human and cattle deaths by lightning and are led to a teenage boy who is the only survivor out of five people recently hit by lightning strikes.

In the midst of a psychic sideshow while on a murder case, Mulder and Scully enlist the help of a man who may have a true psychic ability to foresee how people will die to help the agents catch a man killing fortune tellers.

Nobody takes much notice when a death row inmate vows on the electric chair to come back from the dead and kill five men who have wronged him during his time in prison, until a guard is mysteriously murdered in the former inmate's cell.

A man with a genetic abnormality who must prey on overweight women in order to suck the fatty tissue from their bodies, begins to meet his victims through internet chat rooms.

After a suicide attempt and multiple murders at a military hospital, Mulder and Scully meet a quadruple amputee who has gained the power of astral projection and is taking out his personal frustrations on his commanding officers.

Mulder seeks the help of a woman who he believes has a special connection with a young girl who has recently been kidnapped by the same man who held her captive many years earlier.

An investigation into a video of an alien autopsy puts Mulder and Scully in the middle of a conspiracy involving WWII Japanese scientists brought to America to continue their experiments which may shed light on Scully's abduction.

Mulder is trapped inside a train car which contains a suspected alien-human hybrid and also a bomb, while Scully pursues the truth about her abduction and the mystery behind the implant in her neck.

Mulder and Scully swap roles as they pursue a man killing priests that claim to have the wounds of Christ. The agents find and must protect a young boy who may be a real stigmatic. While Scully's faith draws her close to the boy, Mulder is convinced of another explanation.

Widespread panic is caused in a small community after numerous deaths are linked to killer cockroaches, and a government agricultural agency is discovered to have set up a secret experiment involving insects.

A rare planetary alignment causes strange behavior in the residents of a small town, but particularly in two teenage girls who were born at the exact same moment on that date. While investigating the strange occurrences Mulder's interest in the local female detective makes Scully jealous.

A serial killer is captured after a three year manhunt, and he claims an evil spirit is responsible for the crimes. When the killings continue as he sits in jail, Mulder's battle with a former colleague gets more heated when he suggests that something more paranormal may be involved.

A French salvage ship searching for a lost WWII fighter plane unknowingly surfaces an alien which appears in the form of black oil and has the ability to jump hosts. Mulder heads to Hong Kong to investigate the salvage broker who sold the information to the French and he encounters Krycek, who has been selling information from the MJ documents. As Mulder prepares to take Krycek back to the US, the alien makes its way to Hong Kong and takes control of Krycek.

Mulder pursues Krycek (unaware of the alien that has taken over his body) to get back the DAT tape containing the MJ documents. Meanwhile, the shooting of A.D. Skinner uncovers evidence that could lead Scully to her sister's murderer.

Mulder and Scully are asked to help in a case involving Robert Patrick Modell, a murderer possessing the psychic ability to force his will onto people. Due to a brain tumor that is slowly killing him, he is searching for a "worthy adversary" and forces Mulder into a battle of mind over matter.

The unearthing of an ancient Ecuadorian Amaru urn and its removal to America despite protests leads to a series of deaths linked to a shaman spirit released by the urn.

Mulder, Scully and a local Chinese American cop investigate deaths of several Chinese men found to be missing vital internal organs. The clues lead them to a deadly secret lottery run by the Triads in San Francisco's Chinatown district. The game is free to play but losing will cost you more than an arm and a leg.

A alien abduction of two teenagers with endless versions of the same story prompts a science-fiction novelist to to write a book about the incident; however, nobody involved with the investigation can tell him the full story with any accuracy.

During a one-night-stand in the midst of his divorce, A.D. Skinner becomes a murder suspect, and Mulder and Scully return the many favors that he has done for them by analyzing evidence that someone doesn't want uncovered to prove his innocence.

Mulder and Scully investigate a series of disappearances and attacks around a lake where Mulder believes that the local legend about a lake monster may be all too real. Frustrated Scully insightfully confronts Mulder about the futility of their work on the X-Files.

Mulder and Scully investigate a series of murders linked to a mysterious device that alters television signals causing paranoid hallucinations. One of them falls victim to it.

After his mother suffers a stroke under strange circumstances, Mulder searches for a strange, benevolent alien man that possesses miraculous healing powers. With the help from Mr. X, he learns about the involvement of the Cigarette-Smoking Man and uncovers some secrets kept by his parents.

With his mother on a deathbed and the alien bounty hunter in pursuit, Mulder decides to put Jeremiah Smith, the alien healer, in mortal danger for a chance to finally uncover the whole truth behind the alien conspiracy. Meanwhile, the Syndicate suspects that they have a traitor in their midst and set up a trap.

A baby is found buried alive in shallow ground and appears to have birth defects resulting from generations of inbreeding, leading Mulder and Scully to a reclusive family who have a history of inbred children.

After several African-American men are killed and the color is drained from their skin, Mulder learns about the Teliko, an African folktale about a creature who must suck the pigmentation from a persons body in order to survive.

Several kidnappings of young women linked by distorted photographs lead Mulder and Scully to a man who can imprint his darkest fantasies onto undeveloped film and is trying to save the women from the "howlers".

After an FBI raid on a doomsday cult called the "Temple of the Seven Stars", Mulder meets Melissa, a cultist who claims to have known him in a previous life during the American Civil War. Scully believes the woman is a delusional schizophrenic, but Mulder allows himself to be drawn into her fantasies.

After a doctor loses control and kills a patient on the operating table, Scully hypothesizes that it's linked to work-related stress, while Mulder is convinced of a more sinister reason. After he finds a link between the victim and the four witches Sabbaths, he suspects that a nurse may be practicing witchcraft.

The Lone Gunmen reveal the (possibly fake) secret history of the Cigarette Smoking Man to Mulder and Scully; from a young captain in the U.S. Army recruited to assassinate President Kennedy, to becoming the mysterious man in the shadows at the height of a global conspiracy.

Mulder is given a tip about potentially dangerous paramilitary operations on the U.S. soil but during the sting operation is surprised to find out the identity of his mysterious informant - it turns out to be Alex Krycek. Suspicious about his true motives, Mulder reluctantly follows the information provided by Krycek. However, soon he discovers a much bigger conspiracy which takes him to a gulag in Tunguska, Russia where prisoners are being used for experiments involving a substance of alien origin.

While imprisoned in Russia and infected with the Black Cancer, Mulder learns that Krycek is working with the men responsible and everything has been a setup from the start, while Scully and Skinner are called to a suspicious Senate hearing where the only question is the whereabouts of Agent Mulder.

Mulder's dreams help him in finding the body of a little girl which reopens one of his old cases in the Violent Crimes Unit. This leads him to believe that the killer he captured had more victims and that Mulder's sister Samantha may have been one of them.

After a strange yellow rain kills a migrant girl, her family believes that a mythical creature el chupacabra was the cause and that it has manifested itself inside her fiancé's brother, who has since disappeared.

After the body of a decapitated EMT disappears from the morgue and an identical man starts work at the same hospital, Mulder believes that the man has the ability to regrow parts of his body, including his head. The agents soon discover that Betts' body is riddled with cancer and he is able to live in that condition but needs to feed on cancerous tumors to keep up his strength.

While Mulder is forced to take a vacation he leaves Scully with an assignment to keep her busy until he returns. However, she decides to start living and goes on a date with a man who believes that his tattoo talks to him and is telling him to stay away from other women.

Scully's recent failing health is revealed to be an inoperable cancer in her skull, which appears to be common among abductees and she attempts to come to terms with her condition. Meanwhile, Mulder and the Lone Gunmen break into a high-security research lab to find the cure that could save her life.

After a Jewish man is murdered in a Jewish community, his killers are murdered, too. Mulder and Scully have to determine whether someone is exacting vengeance or larger forces are at work.

When a U.S. military general is inexplicably murdered in the back of his limousine, a paramilitary group is suspected. They believe it was a soldier who they liberated from a Vietnam POW camp and is plotting to kill certain corrupt military figures.

While celebrating Scully's 33rd birthday, a strange woman informs Mulder that NICAP member Max Fenig (see Fallen Angel) has recently died in a plane crash. After a visit to the crash site and finding Max's body with radiation burns on it, Mulder suggests that the plane was intercepted by a UFO and is rapidly being covered up by the military.

Mulder is arrested for investigating the plane crash and interfering with a military operation, while Scully is caught in an attempted assassination of Corporal Frish which claims the life of Agent Pendrell. Scully bails Mulder out of prison, and they go to Max Fenig's trailer to find out why he was on the plane. Mulder finds evidence of alien technology and boards a plane with it, but the plane is intercepted mid-flight and it disappears. Mulder is again left with nothing.

A case involving a strange old man warning two scientists of events in the immediate future which come to pass (and the use of their experimental flash-freezing compound that does not exist yet) has Mulder believing that one of the scientists has come from the future to stop his own scientific breakthrough from becoming reality.

Five babies in the same town are all born with tails and the local OB-GYN is blamed for tampering with fertilized eggs. However, Mulder discovers the culprit to be a simple man with a genetic deformity who may have the ability to alter his appearance.

After a swarm of bees mysteriously kill a postal worker in an enclosed restroom, Assistant Director Skinner covers it up by destroying the evidence. In order to complete the task he poses as Agent Mulder, however his deception backfires. When Mulder finds out and confronts him, Skinner reveals that he is working for the Cigarette-Smoking Man in order to obtain a possible cure for Scully's cancer.

After a man sees a woman trapped inside a bowling alley pin setter, he goes for help and finds police standing next to a body of the same woman. Mulder and Scully join the investigation and follow up this lead which the police won't bother with, and they are led to a mentally challenged man who works at the bowling alley.

Covered in blood and suffering from amnesia, Mulder pieces together the events of the last few days, but the trail leads to a double murder that appears to have been committed with Mulder's weapon.

Mulder fights to prove that a discovery frozen in the mountains of Canada is an irrefutable evidence of alien life, but his quest for the truth only leads to more lies and an unthinkable conclusion.