Welcome to Zardoz Week, people. Please check your penis at the door and pick up your free gun on the way in to The Vortex.
For the uninitiated, Zardoz is a 1974 sci fi film written and directed by John Boorman. The story is far from straightforward, but here are the salient points.
It's 2293 AD, and the people of Earth have splintered into two factions: the Brutals and the Eternals. The hapless Brutals are desperate, nomadic, fighting for survival in a post-apocalyptic wilderness - while the immortal Eternals live a cloistered and pampered life of endless luxury and entropy within The Vortex, a safe environment created for them by The Tabernacle, an advanced artificial intelligence.
The Eternals use the more aggressive Brutals as Exterminators, vicious killers and rapists who keep their own people in their place. They are motivated by their God, Zardoz, a flying stone head which gives them munitions in exchange for grain. Zardoz is actually the creation of Eternal Arthur Frayn, and is little more than an elaborate prop to maintain the status quo.
Zed, an Exterminator, stows aboard the flying head of Zardoz and penetrates The Vortex, the first Brutal to do so. Although he is assumed to be little more than an animal, he is, in fact, the result of Frayn's experiments in eugenics - a genetically mainipulated Nemesis designed to destroy the sterile decadence of The Vortex once and for all...