A skeleton is found in a trawler that sank several years earlier. The metal hatch concealing the skeleton was locked from the outside, pointing to a crime. Meanwhile, the security manager of a canning factory is murdered in his home.

An anaesthetist is murdered in her bathtub as the apartment of a cosmetic surgeon is sacked and the doctor kidnapped. It then emerges that the two worked together in the past with one of their operations resulting in the death of a patient.

A young priest is killed in his rectory and his church ransacked as if the killer was looking for something. Winckler and Faraday initially suspect some young delinquents the deceased priest was helping. Then an unidentified woman is found dead, marked in a strange way.