Mulder and Alex Krycek are assigned to a hostage negotiation. They are briefed by Agent Lucy Kazdin, who explains that a mental patient named Duane Barry has taken his psychologist, Dr. Hakkie, and three other people hostage at a travel agency. Barry demands safe passage for himself and Hakkie to an alien abduction site-although he cannot remember where the site is. Mulder phones Barry and tries calming him. It soon becomes apparent that Barry is well acquainted with hostage crises. Kazdin explains that Barry is a former FBI agent.
     A strange light envelopes the scene. Barry becomes unglued and fires his gun, wounding some of the hostages. Kazdin explains that a power generator blew, but Mulder suspects otherwise. Mulder and Agent Janus volunteer to aid the wounded. They are equipped with a flak jacket and a wire. As Janus tends to an injured man, Mulder speaks with Barry in person for the first time. He strays from the FBI script and talks about UFOs candidly. Barry is taken aback; it's the first time someone given credence to his past experiences. He allows Mulder to trade himself for one of the hostages. As Mulder walks Barry through his UFO encounters, the FBI agents listen in, convinced that Barry is being driven over the edge.
     When Scully is updated of the situation, she urges the FBI to get Mulder out immediately. She explains that in 1982, Barry was shot in the line of duty. The injury effectively destroyed the moral center of his brain, leaving him a pathological liar who suffers from severe delusions. Scully speaks to Mulder via the hidden two-way receiver wired to his body. She urges him to get the hostages away from Barry. Barry concedes to Mulder's request and releases the remaining hostages. Soon after, an FBI marksman shoots Barry.
     Barry is rushed to a hospital. Kazdin tells Mulder that x-rays revealed strange pieces of metal inside Barry's nasal cavity, lending credence to the man's claim that he was kidnapped and tortured by aliens. Scully discovers that the metal is encoded with strange symbols.
     Barry escapes from his hospital room. Without warning, he bursts into Scully's apartment and attacks her.