The skeleton of a young woman is found in a clearing north of Copenhagen. For the ambitious and self-confident Katrine Ries Jensen it is her first own case. At the age of 27, she was appointed deputy head of the homicide squad. As soon as she is at the scene of the crime, her colleague Molbeck searches a nearby run-down caravan on her own, from which an armed man jumps towards him. Katrine also reacts and pulls out her gun, which she must use to protect her colleague. The drug dealer, who has slipped into the caravan and has just been released from prison, is only slightly injured, but Katrine is immediately withdrawn from the case by her boss Magnus Bisgaard. Katrine doesn't just want to put up with this and continues her research while working. In the archives she comes across an article by criminal psychologist Thomas Schaeffer.

A mother and her son are found dead in a noble area of Copenhagen. A short time later, the father's body is also discovered in a harbour basin. It is suspected that the father committed suicide after killing his family. Katrine doubts this theory and once again calls in psychologist Schaeffer, who has separated from his family and wants to work for the police again.

The young African Kaba is found murdered in a Copenhagen prison. Half of the prisoners in this block are sex criminals. Kaba had an affair with fellow prisoner Herning, who was imprisoned for paedophilia. Herning comes under urgent suspicion when it becomes known that he has put Kaba under massive pressure out of jealousy. The investigation also focuses on fellow prisoner Max, a young violent criminal, and the extremely intelligent Martin Høeg, who obviously has the say in the block.

A male body is found. The man was disfigured beyond recognition by blows and stabs. At first his identity cannot be established, but the case reminds Mia of a similar corpse found a few years ago. She puts her colleagues on the right track. This leads to a Russian association that traffics drugs and is in contact with the mafia.

The Russian aupair Beata is found dead in a waste incineration plant. Since there are no useful clues to the murderer, Bisgaard initially suspends the press. While Schaeffer is about to divorce Benedicte, Katrine meets the successful lawyer Simon in a bar, falls in love with him and believes she has finally found the right partner. The case appears in the newspaper, and Bisgaard accuses Schaeffer of having chatted. Schaeffer gets to the head of the responsible journalist and he realizes that the perpetrator himself probably involved the press.

When an unknown perpetrator shoots the student Maria Meyer in a public bus, Schaeffer's last case is his decision for a future with his family. But his last case becomes his most difficult.