After being convicted of a petty crime, a charming rogue named McMurphy contrives to serve his sentence in an airy mental institution rather than in a prison. This, he soon learns, was a mistake. He immediately clashes with the authoritarian head nurse, named Nurse Ratched. Despite her strict reign, McMurphy quickly takes over, leading others out of introversion, staging a revolt, and arranging a rollicking midnight party with liquor and women. But McMurphy's brash insubordination has its consequences; Ratched ultimately triumphs by subjecting McMurphy to a frontal lobotomy.