Albert Basserman (Prof. Heinrich)
Errol Flynn (Sebastian Dubrok)
Ida Lupino (Gemma Smith)
Reginald Denny (Ivor MacLean)
Eleanor Parker (Fenella MacLean)
Gig Young (Caryl Dubrok)
Isobel Elsom (Mrs. MacLean)
Ivan Triesault (Choreographer)
Joan Winfield (Girl)
Jack J. Ford (Double for Albert Basserman)
Helen Pender (Actor/Actress)
Alfredo Sabato (Actor/Actress)
Anthony Caruso (Dino)
Leonard Mudie (Doctor)
Robert St. Angelo (Burly Servant)
Mario Siletti (Gondolier)
Angela Greene (Girl)
Hector V. Sarno (Waiter)
George Humbert (Vendor)
Leon Lenoir (Butler)
Doris Lloyd (Mrs. Cooper)
Ludwig Stossel (Mr. Steinach)
Helene Thimig (Landlady)
George Zoritch (Dancer)
Milada Mladova (Natrova)
Frank Puglia (Guide)
Frank Reicher (Priest)