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.

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.

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.

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.

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.

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.

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 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.

Set in 1989, the story of the founding of The Lone Gunmen is finally told as we see how a straight-laced federal employee, a sex mad AV expert, and a nerdy computer hacker meet Susanne Modeski, a strange woman with evidence of a government conspiracy. When their plan to expose the conspiracy fails and Susanne is captured by a group of men-in-black, led by none other than X, they soon become a paranoid group of government watchdogs.

After not knowing Fox Mulder's whereabouts for the last year, A.D. Skinner and Agent Scully learn he's being held for the murder of a military man he couldn't possibly have killed: Knowle Rohrer, one of the government's secret super-soldiers. With Skinner acting as Mulder's defense, people who Mulder has dealt with during his last nine years as an FBI agent testify on his behalf. But the military tribunal isn't interested in the truth.