Bela Lugosi was originally cast as Dr. Sovac and Boris Karloff as Kingsley/Cannon, but Karloff's interpretation of the gangster was unconvincing and he was replaced by Stanley Ridges. Karloff instead got the role as Dr. Sovac and Lugosi got a minor role, although his second billing remained. (Bojarski, "The Films of Bela Lugosi", 1980) According to contemporary publicity reports, Bela Lugosi was put under hypnosis by technical advisor 'Manly P. Hall' to make his death scene more rea ...[Read Story ]