Béla Lugosi
— Prof Leonide
George Zucco
— Dr. Josef Van Ee
Nat Pendleton
— Bill 'Bull' Raymond
Molly Lamont
— Laura Van Ee
Joyce Compton
— Jane Cornell
Gladys Blake
— Lilly Beth
Roland Varno
— Ward Van Ee
Angelo Rossitto
— Indigo
Douglas Fowley
— Terry Lee
Stanley Andrews
— Pathologist
Lee Bennett
— Rene the Killer
Stanley Price
— Autopsy Surgeon
Dorothy Christy
— Mrs. Williams (uncredited)