Superb but extremely strange sci-fi fantasy released in 1973, starring Sean Connery, Charlotte Rampling and the young John Alderton.
Set in the late 23rd Century in what had once been Northern England, it portrays a post-apocalyptic wasteland in which the dregs of humanity are divided into two camps- the Brutals, who are subsistence farmers, and the Exterminators, heavily-armed gun-toting horsemen whose job it is to keep the Brutal population from getting out of hand. Both groups worship the strange god Zardoz, a fierce-looking bearded head who periodically descends from the sky to issue commandments and declarations.
Zed, a senior Exterminator, has his suspicions that there's more behind Zardoz than meets the eye. Stowing away beneath an offering of grain in the flying head, he finds himself transported into the world of the Eternals, descendants of some of the world's most brilliant scientists who have attained immortality and live in a manor house in an idyllic valley, preserving humanity's achievements with their advanced technology. But the utopia is itself troubled, and change has to come....
A fascinating film, memorable because of it's highly bizarre nature and the superb acting from a very competent cast.