Fight Club (The X-Files)

"Fight Club" is the twentieth episode of the seventh season of the science fiction television series The X-Files. It premiered on the Fox network in the United States on May 7, 2000. It was written by series creator Chris Carter, directed by Paul Shapiro, and featured a guest appearance by Kathy Griffin. The episode plot serves as a "Monster-of-the-Week" story, which is unconnected to the series' wider mythology. "Fight Club" earned a Nielsen household rating of 6.9, being watched by 11.70 million people in its initial broadcast. The episode received mostly negative reviews from television critics.

The show centers on FBI special agents Fox Mulder (David Duchovny) and Dana Scully (Gillian Anderson) who work on cases linked to the paranormal, called X-Files. Mulder is a believer in the paranormal, while the skeptical Scully has been assigned to debunk his work. In this episode, Mulder and Scully run into a pair of doppelgangers, who, whenever they draw near to one another, cause disaster to unfold. Splitting up, the agents try to find out "why" and "what" they are doing.

"Fight Club" was inspired by a "long-lost nugget" of a story that series creator Chris Carter had thought up a while back about "mis-matched twins that had an almost nuclear reaction when they were around each other." Steve Kiziak and Arlene Pileggi—David Duchovny's stunt double and Mitch Pileggi's wife, respectively—were chosen to play the Mulder and Scully look-alikes at the start of the episode. "Fight Club" contained several scenes of intense action that necessitated the use of various stunt doubles and extras.