Jack Nicholson won an Academy Award for best actor in 1975 for which film that was set in a mental institution?

One Flew Over the Cuckoo’s Nest is the answer. Jack Nicholson played Randle P. McMurphy in the 1975 film directed by Milos Forman, adapted from Ken Kesey’s novel, with Louise Fletcher as Nurse Ratched and a psychiatric hospital setting that shaped the film’s central conflict and major Academy Awards success.

Jack Nicholson as Randle P. McMurphy

Randle P. McMurphy is a rebellious patient whose arrival disrupts the routines of the mental institution. Nicholson’s performance centers on McMurphy’s humor, defiance, and resistance to authority inside the hospital. The role won him the Academy Award for Best Actor and became one of the defining performances of his film career.

From Ken Kesey’s Novel to Milos Forman’s Film

One Flew Over the Cuckoo’s Nest was released in 1975 and directed by Milos Forman. The film was based on Ken Kesey’s 1962 novel of the same name. Forman’s adaptation kept the focus on institutional control, individual resistance, and the relationships among patients inside the psychiatric ward.

Nurse Ratched and the Institution Setting

Louise Fletcher played Nurse Ratched, the strict authority figure whose control over the ward brings her into direct conflict with McMurphy. The story is set largely inside an Oregon psychiatric hospital, where daily rules, group sessions, and routines become part of the power struggle. That setting is essential to the film because the conflict depends on McMurphy challenging the institution’s order from within.

The Five Major Academy Awards

One Flew Over the Cuckoo’s Nest won the five major Academy Awards: Best Picture, Best Director, Best Actor, Best Actress, and Best Adapted Screenplay. Nicholson won Best Actor, Fletcher won Best Actress, and Forman won Best Director. That awards sweep made the film one of the rare movies recognized across the Academy’s top categories.