A Clockwork Orange (1971)

The most abrasive film on the route, placed after The Shining so you come to it already used to Kubrick watching violence from a cool distance. Adapted from Anthony Burgess's 1962 novel, it follows Alex, a Beethoven-loving gang leader in a near-future Britain, who is put through a state cure for his brutality, and it asks whether goodness forced on someone counts as goodness at all. Expect explicit sexual violence early on; the film never softens it. After reports of copycat violence and threats to his family, Kubrick himself withdrew it from British circulation in 1973, and it returned there only after his death.