A maniac is once again on the loose in Berlin. A young woman narrowly escapes from the fiend. She is uncooperative with the police, as if she knows the perpetrator and wants to protect him. In fact, her brother and even her husband, one an internist and the other a gifted plastic surgeon, soon become the focus of the murder investigation, as the previous victims have been "expertly" killed and their mouths neatly dissected...