A petty criminal fakes insanity to serve his sentence in a mental ward rather than prison. He soon finds himself as a leader to the other patients—and an enemy to the cruel, domineering nurse who runs the ward.

Jack Nicholson and Louise Fletcher are worthy adversaries in One Flew Over the Cuckoo's Nest, with Miloš Forman's more grounded and morally ambiguous approach to Ken Kesey's surrealistic novel yielding a film of outsized power.

'One Flew Over the Cuckoo's Nest' is praised for the strong performances by Jack Nicholson and Louise Fletcher, and for its powerful depiction of mental health. However, some argue the film lacks the book's complexity and emotional resonance. Despite this, the movie is celebrated for its artistic achievements and cultural influence.