Ina and Hinnerk are performing an Argentine tango before a large audience at the Westerland bandshell when the man sitting next to Carl Sievers suddenly collapses and dies. He is private investigator Edgar Lemberg, a diabetic, and it soon becomes clear that someone has tampered with his insulin syringe. As the detectives hunt for the killer, every one of the PI’s clients is, for now, a suspect.
