A mad killer is loose in Venice's catacombs. He attacks the beautiful women, releasing them into the underworld, kill them and then stop them and add them to his "collection".

New York: Every night the mysterious "Night Owl" goes on the air with her moody radio show. She seems to have an inexplicable influence on some men; several of Julie's friends commit suicide while listening to her voice. She fears for her husband Harry, who becomes more and more distant from her.