“Folie à Deux” is episode nineteen of season five of The X-Files.
In Oak Brook, Illinois, telemarketer Gary Lambert (Brian Markinson), can see an insectile humanoid in his office. No-one else can. He tells the woman he’s speaking to that it’s here.
At the FBI, Mulder and Scully enter Skinner’s office. He wants them to go to Chicago to perform a threat assessment on VinylRight. A telemarketing hub has received an anonymous audiotape manifesto. There was an incident with a gun at another office a few years ago and they don’t want to take the chance. Mulder, his fingers bound from the previous episode, “The Pine Bluff Variant”, asks why the Chicago field office can’t handle it. Because they’d prefer him. Mulder suggests that perhaps the manifesto contains something un usual. It does; talk of a monster stalking the employees.
Outside Skinner’s office, Mulder thinks thus is a waste of time assignment, either because he’s annoyed Skinner or because he’s reached that point where he gets called for everything of this nature. Scully points out they are both assigned and it isn’t necessarily a waste of time. Not for both of them, according to Mulder; he’ll go alone.
Greg Pincus, the boss of the VinylRight office, plays the tape, which was sent to a local radio station, for Mulder. It talks of an evil one preying on people. They can’t see it. It hides in the light. He can see it and he can’t be the only one. They must hunt it down and kill it. Pincus doesn’t recognise the voice but thinks it must be one of his staff. Pincus tells Mulder what the other incident was; he thinks it was over a woman. He thinks it’s a joke but Mulder suggests erring on the side of caution. As Mulder leaves, he calls Scully and asks her to look up the phrase ‘hiding in the light.’ He thinks it’s in an old case file. No, he doesn’t know which one.
Gary is staring at Pincus’s door as Mulder walks away. The woman next to him, Nancy, gets called to Pincus’s office. Lambert tries to convince her not to go. As Nancy enters the office, Gary sees the insect. Then hears a scream, which no-one else does. Nancy comes out, but Gary sees her looking like a walking corpse with white eyes. Nancy says Pincus just wants to say hi to everyone.
Mulder listens to the tape again at the field office as Gary gets a gun ready. Scully calls Mulder; she found a case from 1992. A deacon of a local church was concerned about an evil presence amongst his fellow parishioners. Showed up at mass with four handguns and started wounding people, saying the afflicted would not bleed. He used the same phrase. The man later committed suicide in his cell. Mulder now thinks that Scully should come and help. He heads to the VinylRight office at lunchtime and finds it strangely deserted, even for lunch. Nancy gestures at him to get down but Gary, who has an automatic rifle, sees Mulder.
Scully arrives at VinylRight to find a hefty police presence. She speaks to the Agent in Charge, Rice (Roger Cross). Gary wants to broadcast a stunning revelation on television. He’s barricaded himself in the cafeteria. Scully doesn’t want Mulder compromised.
Gary has separated everyone into two groups. He tells the larger group they need to be afraid of Pincus. When one of the smaller group speaks, Gary says he isn’t addressing them; he’s speaking to the actual people. Mulder speaks up; he wants to hear what Gary has to say. Claiming he was applying for a job. Gary explains that Pincus is a monster, harvesting people’s souls and turning them into zombies. Mulder is trying to get to his gun without Gary noticing. Gary then sees something coming through the vests and fires at the roof. There were police up there.
Rice wants to call Mulder, and does so, despite Scully saying it’s not safe. Scully was right. Gary spots Mulder’s gun when Mulder’s phone rings. One of the so-called zombies goes for Gary and he shoots him. Gary has also found Mulder’s ID. He answers the phone. Scully suggests giving Gary his television wish.
Gary says that Pincus commanded a zombie to kill him. A cameraman is sent inside, which gets the FBI a visual of the cafeteria and a place to breach. Gary is going to shoot Pincus when Mulder intervenes. Then the lights go out and, before the police breach, Mulder sees the monster too.
The hostage crisis is over, but Mulder has also seen the monster. No-one believes him either. Scully suggests he has the folie à deux of the title. ‘Madness for two’; a shared delusion. Mulder certainly sounds like he’s gone crazy. The Pincus monster doesn’t help matters either.