Zardoz (1974)

Watch Zardoz: 2293. Zardoz, an unseen "God" who speaks through an idol, a large stone statue of a head, leads a barbaric race called the Brutals, who live a harsh existence in the Outlands. Zardoz tells the Brutals that once they die, they will be transported to the Vortex, where they will live happily as immortals. He has armed a small group, the Exterminators, with guns, as Zardoz's philosophy is that killing is good, and procreation is the root of all that is bad. In reality, Zardoz is Arthur Frayn, from a competing, more advanced race, called "the Eternals", who live in paradise in the Vortex. The Eternals truly are immortal as they do not age and their bodies undergo reconstruction if they "die"....