Ingrid Bergman character Dr. Constance Petersen
Gregory Peck character John Ballantine
Michael Chekhov character Dr. Alexander Brulov
Leo G. Carroll character Dr. Murchison
Rhonda Fleming character Mary Carmichael
John Emery character Dr. Fleurot
Norman Lloyd character Mr. Garmes
Bill Goodwin character House detective
Steven Geray character Dr. Graff
Donald Curtis character Harry
Wallace Ford character Hotel masher
Art Baker character Det. Lt. Cooley
Regis Toomey character Det. Sgt. Gillespie
Paul Harvey character Dr. Hanish
Jean Acker character Matron (uncredited)
Irving Bacon character Railway Gateman (uncredited)
Richard Bartell character Ticket Taker (uncredited)
Harry Brown character Gateman (uncredited)
Joel Davis character John Ballantine as a Boy (uncredited)
Jacqueline deWit character Nurse (uncredited)
Edward Fielding character Dr. Anthony Edwardes (uncredited)
Alfred Hitchcock character Man Leaving Elevator (uncredited)
Teddy Infuhr character John Ballantine's Brother (uncredited)
Victor Kilian character Sheriff (uncredited)
George Meader character Hallett - Railroad Clerk (uncredited)
Matt Moore character Policeman at Train Station (uncredited)
Constance Purdy character Dr. Brulov's Housekeeper (uncredited)
Addison Richards character Police Captain (uncredited)
Erskine Sanford character Dr. Galt (uncredited)
Janet Scott character Norma Cramer (uncredited)
Clarence Straight character Secretary at Police Station (uncredited)
Dave Willock character Bellboy (uncredited)