Blood Of The Vampire.

Dr. John Pierre (Vincent Ball) is convicted of "malpractice leading to manslaughter" after an emergency blood transfusion, which has never been done successfully, fails, killing his patient. As John's fiancée Madeleine (Barbara Shelley) watches, John is sentenced to life imprisonment in a penal colony. But instead he's sent to a Prison for the Criminal Insane, run by Dr. Callistratus. John grows increasingly uncomfortable with his work because the blood is from unwilling inmates, many of whom die.