Nurse Mildred Ratched is the main antagonist of the 1975 film One Flew over the Cuckoo's Nest. She is the cold, heartless, tyrannical nurse of the mental institution who limits provisions and facilities and takes them away from anyone who inconveniences her. She is assisted by her fellow nurses and three black men.
She is played by Louise Fletcher in the film.
Nurse Ratched both beat and lost to McMurphy at once; though he took away her voice by throttling her, she had him knocked off and lobotomized.