"An experiment on a simpleton turns him into a genius. When he discovers what has been done to him he struggles with whether or not what was done to him was right."
Cliff Robertson
as Charlie Gordon
Claire Bloom
as Alice Kinian
Lilia Skala
as Dr. Anna Straus
Leon Janney
as Dr. Richard Nemur
Ruth White
as Mrs. Apple
Dick Van Patten
as Bert
Edward McNally
as Gimpy
Barney Martin
as Hank
William Dwyer
as Joey
Dan Morgan
as Paddy
Marianna Case
as Young Woman (uncredited)
Leon Collins
as Tap Dancer (uncredited)
Harry Cooper
as Conference Attendee (uncredited)
Frank Dolan
as Eddie (uncredited)
Randee Lynne Jensen
as Woman (uncredited)
Ralph Nelson
as Convention Speaker (uncredited)
Donald Warnock
John DeCuir
Production Design
Clem Portman
Recording Supervision
Tom Walker Jr.
Production Supervisor
Charles Rosen
Art Direction
Phil Naso
Hairstylist
Hazel Roy
Costume Design
Shelley Bartolini
Scenic Artist
Henry Spitz
Production Manager
Jack Brown
Assistant Camera
Richard Kuhn
Title Designer
Jim Shields
Sound Recordist
Vin Kehoe
Makeup Artist
Rod Stephens
Post Production Assistant
Stirling Silliphant
Screenplay
Director
Daniel Keyes
Novel
Selig J. Seligman
Executive Producer
Producer
Fredric Steinkamp
Editor
Arthur J. Ornitz
Director of Photography
Ravi Shankar
Original Music Composer