Arthur Edmund Carewe

Professor Bowen

Professor Omega

Professor Darcy

Dr. Rowitz

Suave Man

Dr. Louis Dumont

Ivan Borolsky, aka Jim

Capt. Spicer

Dr. Fried (credits) / Dr. Beaudine (in film)

George Harris

Lieutenant Destin

Harry

Major Anthony Kinsella

Captain Herault

Count Orloff

Maurice Séquineau

Salvatti

Gigberto

Prince Yussuf

Ledoux

Poulet

Kenneth Bellwood

Henri La Flamme

Ramlika

Israelite Slave (uncredited)

Svengali

Paul Savelli

Prince Ferdinand

Duke d'Alba

John Brainerd