Deliverance is a well-loved classic of the movie screen, but most people don’t know it had a different ending originally. Yes, it seems that in the original version, the guys who make it out of the rafting vacation get arrested by the police for killing the hillbillies, and then they go to jail, where in the last scene, other prisoners force them to: “Squeal like a pig!”
Movie preview audiences rejected this unhappy ending however, and we get the one everybody knows today. And this forced alteration of his masterpiece so enraged John Boorman that he made Zardoz to get revenge on the movie-going public.
But Boorman was still mad after that, so he made Exorcist II: The Heretic next for a further revenge on movie audiences. (He made up to us with it with Excalibur, though.)
(Just kidding. Although this might well have been the ending in real life.)
(Just kidding. Although this might well have been the ending in real life.)