With his human nature and good-natured character, Police Master Johannes Wilke has everything under control. For this reason, he can afford to enjoy a glass of schnapps and play chess on the phone while on duty. Both his colleague Benthin and Pastor Petersen are not at all happy with such an approach to the job. But when a floater, a naked bather and a thieving tipple brother turn up, Wilke puts his beloved chessboard to one side...