Max Ballauf and Freddy Schenk are on duty on the banks of the Rhine in the early morning. A man's body was washed up here. He was a mechanic on board a pleasure boat and apparently involved in a fight shortly before his death. When Chief Inspector Schenk contacts the captain of the "Agrippina", the case takes a dramatic turn: Daniel Huberty, a former ship, is on board the ship that has just cast offHigh school teacher who now threatens, "I'll blow up the ship if you don't comply with my demands." He demands justice. It did not exist in the court case when he was sentenced to imprisonment for a liaison with an underage student. Now the people he considers guilty of having destroyed his existence are to be brought on board...