The X-Files was a very popular 1990s science fiction television series created by Chris Carter, appearing on FOX and later in syndication. Premiering in 1993, its ground-breaking success was due mostly to its stars, David Duchovny and Gillian Anderson, who starred as a pair of FBI agents, Fox Mulder and Dana Scully, tasked with investigating paranormal phenomena. With plots spanning alien conspiracy theories and high-level governmental cover-up, the show related well to the episodic mainstream of shows such as The Outer Limits and The Twilight Zone and the cult show Twin Peaks (in which Duchovny appeared as a cross-dressing DEA agent). The series became a surprise run-away success, with a hardcore cult following (fans are known as "X-Philes") as devout as Star Trek 's Trekkers.
The X-Files struck a unique balance between rationalism and mysticism, horror and wonder; its stories were told like police procedurals investigating the paranormal.
The series popularized the catch-phrases "Trust No One" and "The Truth Is Out There," and fosters a huge fan-based following to this day.
Fans commonly divide X-Files stories into "Mythology" episodes, which concern a coming alien invasion, and "Monster" episodes, which deal with unrelated strange creatures.
In 1998 the series produced a motion picture, The X-Files: Fight The Future, which attained considerable critical and box office success. The movie itself was a complement to the central mythology of the show, yet at the same time appealed to many who were unfamiliar with The X-Files. As a result of the movie's success, the fan following of The X-Files significantly increased.
Over the course of the next few years, the show would undergo several changes by way of both character growth and plot direction. One of the central mythologies of the show, Mulder's search for his sister, would finally be resolved, as well as a few turns of events involving the ever-deepening bond between Mulder and Scully and the dynamic between the two characters. Whether they "should" or "shouldn't" consummate their relationship was the subject of great debate among the fan community for many years, and is still subject to scrutiny despite the now-apparent resolution of this question. Even now there remains a thriving online community devoted to debating The X-Files, its myths and monsters.
The show completed its ninth and final season with the episode "The Truth", which first aired on May 19th, 2002. While David Duchovny did not wish to return (his involvement was limited in Season 8), Gillian Anderson maintained her starring role, interacting with supplementary characters John Doggett and Monica Reyes, played by Robert Patrick and Annabeth Gish, respectively.
Although the television series itself has officially come to a close, it is very likely the involvement of the original stars is not yet over. Both Gillian Anderson and David Duchovny have expressed interest in doing additional movies, the next probably to premiere in the Fall of 2004.
"The Lone Gunmen", a trio of nerdish government watchdogs who occasionally assisted Mulder and Scully, had their own short-lived TV series.
The X-Files inspired numerous other TV series, including Strange World, Burning Zone, Special Unit 2, Mysterious Ways and Dark Skies, many of which did not enjoy the same popularity or following as The X-Files has achieved. Fox also produced a companion series based upon The X-Files entitled Millennium. The storylines of Millennium and The X-Files occasionally crossed over, with Scully and Mulder making cameo appearances in at least one episode of Millennium, and the protagonist of Millennium appearing in The X-Files to tie up loose ends after Millennium was abruptly cancelled.