The Wicker Man (1973)

Edward Woodward stars as Sergeant Howie, a naive young police officer sent to Summerisle, a secluded island off the coast of Scotland, to investigate the disappearance of a young girl named Rowan. When he arrives there, he finds a very tight-knit community that is mistrustful and hostile to outsiders. No one is willing to even acknowledge Rowan's disappearance. Soon, Howie begins to realise that the town might, in fact, be a strange pagan cult, one given to unbridled sexuality and possible human sacrifice. A classic of British cinema!