During his long career, American-born British film director Terry Gilliam has worked on a number of projects which never progressed beyond the pre-production stage under his direction. Some of these productions fell into development hell or were cancelled. The following is a list of projects in roughly chronological order.
20th century
Theseus and the Minotaur
Right after he finished Jabberwocky (1977), Gilliam’s next film project would be Theseus and the Minotaur, based on Greek mythology. The film was shelved when Gilliam chose to make Time Bandits (1981) instead.
Watchmen
In 1989, Gilliam and film producer Joel Silver unsuccessfully attempted to make a film adaptation of Alan Moore's Watchmen. Gilliam was reportedly Moore's first choice to direct the film. Gilliam tried to make the film again in 1996 but was unsuccessful.
A Scanner Darkly
In the early 1990s, Gilliam attempted to make a film adaptation of Philip K. Dick’s A Scanner Darkly.
The Defective Detective
In 1992, it was reported that Gilliam was going to make The Defective Detective next after The Fisher King (1991), only to abandon it in favor of making a Don Quixote film. Then, Gilliam worked on The Defective Detective again to only to reject it in favor of directing 12 Monkeys (1995) instead. Then, the Los Angeles Times reported in 1996 that Gilliam was working on The Defective Detective script with Richard LaGravenese. According to the L.A. Times, the story was "about a middle-aged New York cop who’s having a nervous breakdown and ends up in a fantasy world." The film was to have been produced by Scott Rudin and Margie Simkin and be distributed by Paramount Pictures. Nicolas Cage was to star in the film. In addition to Cage, Bruce Willis, Cameron Diaz and Nick Nolte were attached to the project. Danny DeVito was also attached to the project. Gilliam claims that Sean Connery was also involved. In February 1997, Paramount put the film in turnaround.
In June 2015, Gilliam hinted that The Defective Detective could possibly be made as a miniseries from Amazon Prime Video. Variety reported in November that same year that Gilliam and LaGravenese regained the rights to the script from Paramount and "reworked it as a six-hour miniseries."
A Connecticut Yankee in King Arthur's Court
It was reported in 1993 that Gilliam was going to direct a film adaptation of Mark Twain's A Connecticut Yankee in King Arthur's Court for Warner Bros. and producer Jerry Weintraub, with the script written by Robert Mark Kamen. The film got cancelled when financing fell through.
A Tale of Two Cities
In 1994, Gilliam attempted to make a film adaptation of Charles Dickens' A Tale of Two Cities with Mel Gibson starring. However, Gibson dropped out of the project in favor of directing and starring in Braveheart (1995). After Gibson left the project, Gilliam replaced him with Liam Neeson and attempted to make the film via half the initial budget to no avail. Madeleine Stowe was also attached to the project. The film was ultimately shelved due to budget and casting reasons. Gilliam then made 12 Monkeys (1995) instead. When asked in 2009 if he still expressed interest in making the film, Gilliam replied, "Nah. That’s dead. That’s over."
Time Bandits II
In 1996, Gilliam and Charles McKeown wrote two drafts of an unproduced script titled Time Bandits II, which would have been the sequel to Time Bandits (1981). Gilliam was to have produced the sequel and not direct it. In 2001, Gilliam and McKeown attempted to make Time Bandits II as a television miniseries for the Hallmark Channel.
21st century
Good Omens
In 2002, Gilliam attempted to direct a film adaptation of Terry Pratchett and Neil Gaiman's Good Omens. Johnny Depp and Robin Williams were to have appeared in the film as the demon Crowley and the angel Aziraphale respectively. The film never came to fruition. According to Gilliam, the film was cancelled due to the then-occurring aftermath of the September 11 attacks. The story eventually appeared in 2019 under the same name, Good Omens, as a 6-episode series streaming on Amazon Prime Video and aired by BBC Two, but it was directed by Douglas Mackinnon, starring Michael Sheen and David Tennant.