Vincent Bruce, a war veteran, begins working as an occupational therapist at Poplar Lodge, a private psychiatric facility for wealthy people where he meets Lilith Arthur, a charming young woman suffering from schizophrenia, whose fragile beauty captivates all who meet her.

Warren Beatty
as Vincent Bruce

Jean Seberg
as Lilith Arthur

Peter Fonda
as Stephen Evshevsky

Kim Hunter
as Dr. Bea Brice

Anne Meacham
as Mrs. Yvonne Meaghan

Jessica Walter
as Laura

Gene Hackman
as Norman

James Patterson
as Dr. Lavrier

Robert Reilly
as Bob Clayfield

René Auberjonois
as Howie (uncredited)