The Pit and the Pendulum

Francis (John Kerr) visits the gloomy Spanish castle of his late sister Elizabeth's husband, Nicholas (Vincent Price), to learn the reason for her death. Nicholas fears his wife isn't really dead and that her spirit wanders the halls at night. Seems Nicholas's father was a feared leader of the Spanish Inquisition; as a child, Nicholas saw his father torture his mother and bury her alive, and he's convinced Elizabeth has suffered a similar fate.