Brooding Boris plays Doctor Victor Sartorius, an ailing doctor working in Morocco. He teams up with Mona Goya as Lady Yvonne Clifford, in a plot to poison her husband, Sir Charles Clifford so he can collect the 20,000 pounds necessary to save his experiments and his funding. Roger Clifford, the son of Sir Charles has also been marked for death. The only one who can stop the murder plot of Sartorius is Nurse Eve Rowe, played by the beautiful Joan Wyndham. This is one of the few Karloff genre movies from the thirties that is often overlooked and rarely discussed, and there are reasons for this.