This summer there is no holiday for Kommissar Hunkeler. Instead of spending the vacation with his girlfriend Hedwig in Alsace, he has to deal with a mysterious case in the city of Basel: His family doctor, a well-known, liberal politician, has been murdered in her office. Among the suspects are several drug addicts who she supplied with Methadon. Also her rejected and despised son could have had a motive to kill his mother. But Hunkeler's instinct regarding the depths of human psyche leads to another track.