The fourth season of the American science fiction television series The X-Files commenced airing on the Fox network in the United States on October 4, 1996, concluding on the same channel on May 18, 1997, and contained 24 episodes. Following the filming and airing of the season, production began on The X-Files feature film, which was scheduled to be released in 1998 following the show’s fifth season.
The fourth season of the series focused heavily on FBI federal agents Fox Mulder’s and his partner Dana Scully’s investigation of an alien conspiracy, which is protected by the mysterious Syndicate. Midway through the season, Scully is diagnosed with terminal cancer, a result of her previous abduction, and Mulder begins to lose his faith in the idea of extraterrestrials. The season ends on a cliffhanger, with the purported suicide of Mulder.
Debuting with high viewing figures and ranking as the twentieth most watched television series during the 1996–97 television year in the United States, the season was a success, with figures averaging around 20 million viewers an episode. This made it, at the time, the highest rated season of The X-Files to air. The season’s twelfth episode, “Leonard Betts” was chosen as the Fox lead-out program following Super Bowl XXXI, and was viewed by 29.1 million viewers, making it the highest-rated episode in the series’ run. Critical reception from television critics was mostly positive.