Financial broker Burnes asks the chief of the criminal investigation department to come to his office because of a theft. His wife's valuable ring has been stolen. While the police suspect a "normal" burglary, Mr. Burnes' shady past comes to light. Years ago, he was involved in an embezzlement scandal but was acquitted. Another person received a long prison sentence. The burglary was apparently related to this matter. Suddenly, Burnes' marriage to the much younger Florence also appears in a dubious light. A murder under mysterious circumstances compromises a whole series of people. Criminal investigator Lieutenant Schubert is quite surprised by the events of the foggy night of the murder, especially when he comes face to face with the murderer – his driver John.