The X-Files is an American science fiction horror drama television series created by Chris Carter. The program originally aired from September 10, 1993, to May 19, 2002, on Fox, spanning nine seasons, with 202 episodes and a feature film of the same name, before returning with a second film in 2008 and a six-episode tenth season in 2016. The series revolves around FBI special agents Fox Mulder (David Duchovny) and Dana Scully (Gillian Anderson) who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena. Mulder believes in the existence of aliens and the paranormal while Scully, a medical doctor and a skeptic, is assigned to make scientific analyses of Mulder’s discoveries to debunk his work and thus return him to mainstream cases. Early in the series, both agents become pawns in a larger conflict and come to trust only each other and a very few select people. They develop a close relationship which begins as a platonic friendship, but becomes a romance by the end of the series. In addition to the series-spanning story arc, “Monster-of-the-Week” episodes form roughly two-thirds of all episodes.