Picnic At Hanging Rock, Peter Weir, 1975

During a rural picnic, a few students and a teacher from an Australian girls' school vanish without a trace. Their absence frustrates and haunts the people left behind.

One Flew Over the Cuckoo's Nest, Milos Forman, 1975

McMurphy thinks he can get out of doing work while in prison by pretending to be mad. His plan backfires when he is sent to a mental asylum. He tries to liven the place up a bit by playing card games and basketball with his fellow inmates, but the head nurse is after him at every turn.