three of his aging friends and requests that they be his test subjects. Initially they refuse, but one of them, Victor Sondini (Pedro de Córdoba), later changes his mind after Dr. Garth pays him a visit. Just as he is about to administer the serum, Garth is again overcome by the impulses of the executed prisoner and strangles his friend. Finally beginning to realize what he has been doing, Garth visits one of his other friends, George Wharton (Wright Kramer), to confess his crimes and request that he be his final test subject before he turns himself in. Wharton attempts to call for help, but Garth kills him before he can do so. As the bodies begin to pile up and Dr. Garth's behavior becomes more erratic, Martha begins to suspect that something is up and confronts her father. Garth begs her to leave as he continues to fight the impulses of the murderous blood, but she refuses and he comes at her. She faints and Dr. Garth flees. In the final scene, Dr. Garth, now being pursued by the police, approaches the prison where he had been incarcerated. The warden admits him, but Garth immediately makes aggressive movements toward the armed guard at the gate. The guard shoots him, and as he is dying the doctor admits that he committed suicide in order to prevent himself from killing anyone else. Cast Boris Karloff as Dr. John Garth Evelyn Keyes as Martha Garth Bruce Bennett as Dr. Paul Ames Edward Van Sloan as Dr. Ralph Howard Ben Taggart as Warden Thompson Pedro de Córdoba as Victor Sondini Wright Kramer as George Wharton Bertram Marburgh as Stephen Barclay Don Beddoe as Capt. McGraw Robert Fiske as District Attorney Kenneth MacDonald as Anson, Prison Guard Frank Richards as Otto Kron – Convict See also List of American films of 1940 Boris Karloff filmography Notes References External links 1940 films 1940 horror films American science fiction horror films 1940s science fiction horror films 1940s English-language films Films directed by Nick Grinde Columbia Pictures films American black-and-white films 1940s American films