Investigations into the new case of Commissioner 12 are making waves: in the M.S. cabin. Seestern appears instead of a blind passenger of the dead sailor Wojtech Pilsudksi. The ship belongs to the shady captain Jürgen Wimmer, who is questioning the situation in the cloudy. Forensic doctor Dr. Lara Krüger finds many bruises and a strong smell of alcohol in the victim. Did the sailor fall or was it murder? Even in the private life of the „ Rentnercops " it goes haywire. Loner Bielefelder is dealing with an intrusive neighbor and Francesca wants to take a tango course with Klaus. Quickly away! But when examining the crime scene, there is suddenly a red Mustang on the quay, who races away at high speed when the two inmates see the police.
The suspicion of the „ Rentnercops " is aroused, especially when Hui Ko finds out who the PS-strong sledge is allowed on. Frank „ Frankie " Schoppe, penalized for drug dealing! Cocaine, ketamine, methamphetamine – not a substance that he would not have given away. Brother Elvis also appears to be involved in the case. Were the Schoppe brothers as drug couriers at the port? And is Frankie just a little fish in this case or does blood stick to his hands?