When former criminal Gaudl discovers the strange behaviour of his son-in-law Professor Horacek, he becomes worried about his daughter Hedwig and starts to gather evidence. When his suspicions seem justified, he visits his former colleague and friend, Lieutenant Colonel Maca. Little does Hedvika know that her husband is having an affair with their lodger Daniela. When her husband tells her of his intention to divorce her, she makes a scene at the least convenient time, while driving the car. This causes a crash in which a young hitchhiker is killed. She persuades her husband to drive away from the scene of the accident. In doing so, she takes a picture of her husband hiding the young girl's corpse in the woods. She now has a gun in her hand to blackmail the man, who decides to settle the matter once and for all.