"Tempus Fugit" featured guest appearances by Joe Spano, Tom O'Brien and Brendan Beiser, and saw the return of Scott Bellis as alien abductee Max Fenig.
The show centers on FBI special agents Fox Mulder (David Duchovny) and Dana Scully (Gillian Anderson) who work on cases linked to the paranormal, called X-Files.
In the episode, Max Fenig—an old acquaintance of Mulder—is found dead following an airplane crash, which Mulder believes to have been caused by a UFO attempting to abduct Fenig.
"Tempus Fugit" was conceived when the series' special effects supervisor Dave Gauthier constructed an elaborate rig capable of simulating a crashing airplane.
"Tempus Fugit" received mixed to positive critical reception, and earned the production crew two Emmy Award nominations, including a win for Outstanding Sound Editing For A Series.
Mulder theorizes that the plane was forced down by aliens attempting to abduct Max; the NTSB team, led by chief investigator Mike Millar (Joe Spano), dismisses his claims.
Meanwhile, Scott Garrett, a Man in Black posing as an NTSB investigator, steals the zip gun from the assassin's body and erases his face and fingerprints with acid.
[1] During the production of the third season, special effects supervisor Dave Gauthier constructed an elaborate mock-up of a Boeing 737 airplane in order to be able to simulate a crash.
When conceiving of the episode, the desire to add to Fox Mulder's emotional involvement by having someone he knew on board led to the writers bringing back the character of Max Fenig to be that person.
[3] Scott Bellis, who had previously portrayed Fenig in the first season episode "Fallen Angel", had auditioned for other roles on the show in the interim, but had always been rejected by the producers because his character was felt to be too memorable.
Bellis met series star David Duchovny at a gym several times, and learnt from him that the character of Max was being considered for a two-part episode.
[3] Gauthier's 737 rig—which required 400 U.S. gallons (1,500 L) of hydraulic fluid to mimic an airplane fuselage movement across multiple axes in order to better simulate turbulence; it could rotate 22 degrees each way about its length, and move four feet to either side.
[4] The show's producers wanted the plane crash site and investigation to be as authentic as possible, so they used a National Transportation Safety Board official to act as their technical advisor on the episode to ensure that everything was properly recreated.
Director Rob Bowman admitted that the episode exceeded its given budget, noting that Carter would often defend him from Fox studio officials angry at his production costs.
However, Vitaris felt that the fleeting use of guest star Scott Bellis was "a waste", and that the discovery of an alien corpse towards the end "robs this story of any ambiguity".