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.

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".