Für Mord kein Beweis (1979)

Mr. Zinn intends to pick up his wife Steffi from the hairdresser’s, but misses her. At home, the couple have such a loud argument that the neighbor’s daughter, exasperated, bangs on the wall. Mr. Zinn goes to the tavern across the street, run by Zumseil, who also offers him a bed for the night. The next day, Zinn does not find his wife in the apartment. He suffers a breakdown. About a week later, Steffi Zinn’s naked body is found in a lake. Captain Lohm is assigned to investigate the case. Everything points to suicide. Steffi Zinn drowned, and there are no signs of violence. Only her broken fingernails and a cotton thread on one of them, which might have come from a bandage, make the investigators suspicious. The investigation soon stalls, however. Zinn had found his wife as a refugee child in Königsberg and brought her to Berlin to live with his grandmother. When the grandmother died, Zinn married the young woman. Neither of them has any friends or relatives, because Zinn’s profession—he bred rats for research—repels people. Zinn also insists that Steffi did not have an affair. The body is released for burial. At the funeral, Lohm spots a strange man in the distance, but he flees as the captain approaches. Meanwhile, Zinn finds a letter in his apartment from a man named Lorras and goes to see him. It becomes clear that the two know each other from the past. Zinn’s real name is Dr. Leibchen, and during the Second World War he was in charge of inhuman experiments at Dachau concentration camp. Lorras worked for him. The experiences of those years have broken Lorras. He has a panicked fear of water and believes that he himself bears some responsibility for every murder that takes place. Some time earlier, he had told Steffi about her husband’s machinations, but Zinn had always denied them to her. A little later, Lorras is found dead. He was poisoned with hydrocyanic acid. Lohm finds a confession on the dead man stating that Lorras killed Steffi Zinn. The victim’s clothes, which had been missing until then, are also found in Lorras’s cellar. The case seems solved, but Lohm cannot find a motive. Zumseil, the tavern owner, exposes Zinn’s claim that he did not know Lorras as a lie. Lorras had been in his tavern when he spoke to Steffi Zinn and asked her to pass his greetings to Zinn. He also mentioned the name “Dr. Leibchen.” In Lorras’s apartment, Lohm finds military letters in which Lorras complains, among other things, about his cold-hearted and inhuman superior. Lohm also finds Zinn’s file, documenting his activities during the war. Zinn is arrested for his war crimes. Lohm still believes that Zinn instigated Lorras to murder Steffi. It is only a medical report that establishes that Lorras, because of his panicked fear of water, could never have committed a drowning murder. Zinn’s employee, Mrs. Zoll, provides the final clue. The day before the argument between the spouses, Zinn had to have his arm bandaged because of a rat bite. The neighbor’s daughter and her boyfriend say that during the argument in question, they heard two male voices in addition to Steffi Zinn’s: the voice of the man arguing, and another voice defending the argument after they indignantly banged on the wall. This makes Lohm realize that Zinn had played the argument from a tape recording, and that Steffi was already dead at the time. When Lohm also proves that Zinn murdered his wife, Zinn is surprised, since he will receive the maximum sentence anyway for his other crimes.