In the early 1990s, TV writer Chris Carter had been working on shows like Rags to Riches, The Magical World of Disney, and A Brand New Life. Growing weary of writing for wholesome style sitcoms, he wanted to branch out into something new. Something mysterious, otherworldly, dare we say, spooky.

When Fox gave him the chance to develop and produce a show, Carter created The X-Files. Debuting 30 years ago on September 10, 1993, the series centered around the FBI’s strangest cases, known as X-Files. Those cases were investigated by Special Agent Fox Mulder (David Duchovny), a criminal profiler and believer in the paranormal, and Special Agent Dana Scully (Gillian Anderson), a clinical medical doctor and skeptic. They looked into everything from monster of the week episodes about strange occurrences to longer story arcs about orchestrated alien invasions.

While brainstorming TV show ideas, Carter read a report that 3.7 million Americans were convinced that they had been abducted by aliens. Building on that, he considered investigations into the Watergate scandal, and the premise of the horror TV series Kolchak: The Night Stalker, for the initial pitch.

Fox wasn’t on board with the concept at this point, so Carter enlisted the help of Daniel Sackheim (a producer on NYPD Blue) to improve on the concept. At this stage, Carter fine-tuned the investigatory aspects through the inspiration of the British series Prime Suspect and the documentary The Thin Blue Line. Drawing inspiration from The Silence of the Lambs, Carter decided to frame the series around FBI agents, which would be more plausible than a single police precinct consistently dealing with the supernatural. Carter was determined to keep Mulder and Scully in a platonic relationship, which he based on Emma Peel and John Steed from The Avengers series.

Writers and producers on The X-Files have named many other titles that inspired them. For the paranormal/horror themes, they drew from titles like Close Encounters of the Third Kind and The Thing; the police procedural/investigatory aspects were inspired by All the President’s Men and JFK; it also has the adventures and exploration of Raiders of the Lost Ark; and moody dark atmosphere of Twin Peaks.

The X-Files would end up running for 218 episodes, with a nine-season run from 1993 to 2002, then a two-season revival from 2016 to 2018, plus two movies based on the show.