n the cabin of a beauty salon, a customer suffocates. An employee has previously observed how an unknown person has left the cabin of the dead. The best friend of the dead, sparkling wine manufacturer Karla Wilke, is in the neighboring cabin at the time of the crime. Coroner Dr. Graf confirms Richie's suspicions: The customer was murdered. While Moser interrogates Karla Wilke, Rex escapes an assassination attempt at the last second. Suddenly, lawyer Dr. Rudolf Baumann appears. The attractive Baumann is not only Mrs. Wilke's lover, but he also had an affair with the dead. His alibi for the time of the crime is not verifiable. Moser tracks down the perpetrator, he is sure: The murderer has made a serious mistake, he has confused his victim. Mrs. Wilke's life is in danger...