Hotel by the Hour(1970)

Original title: Das Stunden-Hotel von St. Pauli

A murder has taken place in the “Ostend” hotel in St. Pauli and Inspector Canisius is called to the crime scene. Mentally shaken, Canisius takes up the investigation. A wide variety of guests and couples were at the hotel that night, and anyone could be the perpetrator. Canisius experiences his most difficult case, in constant fear for his son.