A real baboon on the set attacked a double dressed in an ape suit who was portraying a baboon.

According to John Boorman, Sean Connery had a very hard time finding work after Diamonds Are Forever (1971). Boorman was allegedly able to hire Connery for $200,000.

The opening sequence is an introduction added by John Boorman, at the request of 20th Century Fox executives, to help the audience understand the film.

John Boorman made this film after his project to film J.R.R. Tolkien's "The Lord of the Rings" was canceled.

John Boorman used Irish Travellers as extras. He said that they were the best extras that he'd ever had, extremely pleasant and reliable. He cast them, because he thought they looked like people who'd actually lived an outdoor life.

Radio spots (available on the DVD) were narrated by Rod Serling.

Reportedly, Charlotte Rampling looked forward to her sex scene with Sean Connery, then was disappointed when it was over and done with so quickly.

The Irish government initially refused to allow the production team to import prop guns because of terrorist attacks occurring at the time.

To help keep costs down, Sean Connery used his own car and drove himself during the production. John Boorman then gave him half the money that had been budgeted to hire him a car and driver. The idea was Connery's, according to Boorman.

To make the shots of the stone head move into the mouth accurately, the camera was placed at the mouth and tracked backwards, and the film reversed in the lab.

Cinematographer Geoffrey Unsworth filmed scenes with the lens wide open, fog filters on the camera, and smoke machines on set to achieve a diffused, impressionistic look. It worked on first-generation prints, but when the film was duplicated for release the image quality was so bad it was almost unusable. The studio forbade any cinematographers from using that process on future films.

The exterior shots at the opening of the movie were taken right next to John Boorman's house in Ireland.

This film is listed among The 100 Most Enjoyably Bad Movies Ever Made in John Wilson's book "The Official Razzie® Movie Guide."

The "hand print" cave art in the end sequence refers to examples of the oldest kind of cave art ever found, such as the hand stencils in Spain's El Castillo cave.

Sean Connery's reported salary, $200,000, was one-fifth of the film's $1 million budget.

Burt Reynolds, a big box-office star at the time, who had previously worked with John Boorman on Deliverance (1972), was the first choice for the lead role of Zed. He bowed out due to illness.

Sean Connery appears in drag, as a bride in one scene. Reportedly, Connery initially felt uncomfortable about doing the cross-dressing sequence.

Zed's revolver is a .455-cal. Webley-Fosbery, a unique pistol because it is semi-automatic. The recoil turns the cylinder and cocks the hammer.

The opening title card reads "Set in the year 2293". Originally John Boorman was going to set the movie about five years into the future, which would have been the late 1970s.

Three of John Boorman's children appear in the flashback scene concerning the founding of the tabernacle: Daisy Boorman, Telsche Boorman, and Katrine Boorman.

The Renegade's rest home was filmed inside the work canteen of Ardmore Studios in Ireland, with some minor modifications.

Ian Christie of the Daily Express said in his review "if this is intellectual thinking, then Donald Duck deserves the Nobel Prize".

The picture is considered a cult film and is included in Danny Peary's book "Cult Movies 2" (1983).

John Boorman offered Richard Harris the lead role of Zed. Harris never responded.

Charley Boorman recalled that Sean Connery stayed at the Boorman family home in Annamoe, County Wicklow, Ireland, for the duration of the shoot. At the end of each week, Connery would pay John Boorman's wife "rent" money, to cover the costs of keeping him.

In Papua New Guinea, during filming of Charley Boorman: Sydney to Tokyo by Any Means (2009), John Boorman's son Charley Boorman met tribesmen who wore masks similar to those seen in this film.

The film features five identifiable groups of people: Brutals, Eternals, Renegades, Apathetics, and Exterminators.

Director Ben Wheatley is a huge fan of the movie.

The Brutals live in the Outlands. Sean Connery later starred in Outland (1981), another science-fiction picture.

The scene in which Zed and Consuella turn into skeletons had to be shot three times. The first time, the film was damaged. The second time, a studio helper accidentally exposed the negatives. Sean Connery and Charlotte Rampling were extremely annoyed because the make-up took a very long time.

John Boorman: the slave forced into farming, who Sean Connery shoots. Boorman was shot with a blank, but wadding became embedded in his forehead, and took several days to come out.

The title is a reduced conflation of the phrase the "Wizard of Oz" by removing the first two "Wi" letters from the word "Wizard" and also the middle word "of" thereby forming the word "Zardoz". "The Wizard of Oz" is L. Frank Baum's famous character that appeared in his series of "Oz" books filmed in various movie and television productions. Its relevance is revealed later in the picture.