The X-Files

The X-Files was a science fiction television series on Earth, about FBI agents who investigated alien and paranormal events.

The BBC stopped showing The X-Files in 1997 "due to recent events" (an actual alien invasion). (PROSE: The Dying Days)

In 1999, Brigadier Lethbridge-Stewart called his group of investigators "UNIT's X-Files." The Fifth Doctor was unfamiliar with the programme. (PROSE: The King of Terror)

An older version of Peri Brown living in Los Angeles in 2009 once falsely posed as a secret agent to her younger self, claiming to work for an agency known as "the X-Files." When she tried the ruse on the Fifth Doctor, with whom her younger self was travelling, the Doctor replied that while he had enjoyed the programme, it was never as good after David Duchovny left. (AUDIO: Peri and the Piscon Paradox)

Ace's younger brother Liam McShane was a fan of the series. (AUDIO: The Rapture)

Among a long list of actions the Xlanthi considered to be a violation of the law and punishable by a brutal death was "fancying Scully out of The X-Files." (PROSE: Beige Planet Mars)

Sarah Jane Smith once asked Mike Yates, who had invited her to investigate a haunted house, why he didn't call "Fox and Dana" instead. (PROSE: Housewarming)

Clive Finch had an X-Files mug. (PROSE: Rose)

Eugene Jones had an The X Files VHS in his bedroom. (TV: Random Shoes)

PC Andy Davidson sarcastically referred to Jack Harkness and Gwen Cooper as "Mulder and Scully." (TV: End of Days)

In an alternate timeline, Lizzie Corrigan told Maxwell Edison that her Psychic Investigation Group (PIG) colleagues were fans of the series. (AUDIO: The Eternal Summer)

When Alan Jackson spoke to Maria Jackson about aliens in 2008, he told her that he was new to "all this X-Files stuff". (TV: The Lost Boy)

When Ocean Waters and Melvin Minton were looking for aliens in 2010, Clyde Langer called them "Mulder and Scully." (TV: The Vault of Secrets)

In 2016, Izzy Sinclair bought Maxwell Edison the complete X-Files on Blu-ray for his 60th birthday. She later knocked out Josiah W. Dogbolter with the Blu-ray box set. (COMIC: The Stockbridge Showdown)

Panda called the Forge a group of "cut price Mulder and Scullys". (PROSE: Project: Wildthyme)

Donna Noble claimed that she and the Tenth Doctor were "working for the X-Files" when questioned by Commodore William Jarman in 1940. Jarman later contacted the British government, who informed him that the group did not exist. (AUDIO: The Nemonite Invasion)

Behind the scenes

 * The BBC created a Doctor Who themed take on the classic "I Want to Believe" poster from Mulder's office from The X-Files, swapping out the UFO for The Doctor's TARDIS.
 * A similar poster is featured on the cover of Doctor Who: The Thirteenth Doctor #8 Cover A.
 * Redacted fanart 4.jpgarly, a piece of Redacted fanart reposted by the [[Doctor Who Twitter account|Doctor Who Twitter account]] featured a reference to the same poster, though retaining the UFO from the original.
 * During the 2001 DVD commentary for Spearhead from Space, Nicholas Courtney was amused by the fact that visible on a shelf behind the Brigadier's desk was a file labelled "X" — in other words, "the X file."
 * The X-Files was primarily filmed in Vancouver, Canada, the same city that the 1996 Doctor Who movie was filmed. Both productions were active at the same time, with cast and crew of the TV movie having recounted in interviews occasional encounters and shared spaces with the TV show's activity.
 * Gary Russell has cited The X-Files as a major source of inspiration for the novel The Scales of Injustice. The novel's Pale Man echoes the programme's Cigarette Smoking Man. Even the Pale Man's subordinate, the Blond Man, is based on the Crew Cut Man, Cigarette Smoking Man's subordinate.
 * A number of Doctor Who actors appeared in the series, including Mark Sheppard, Deep Roy, Gordon Tipple, Will Sasso, Catherine Lough, Bill Croft, Michael David Simms, Dave Hurtubise, Lesley Ewen, Lauren Ambrose, Frances Fisher, Benito Martinez, Alan Dale, George Murdock, Paul Hayes, Robert Moloney and Jane Perry. Murdock and Milton Johns appeared in the film The X-Files: Fight The Future. Paul Frift worked on both series 8 of Doctor Who (as producer) and The X-Files: Fight the Future (as unit production manager). John Shiban was a writer and producer on the series.