When a girl is raped on campus in circumstances identical to an unsolved case from 10 years previously, inspector Donckers calls upon her former psychological criminology Professor T to help crack an impossible case. Simultaneously expert and eccentric, his curious methods ruffle a few feathers along the way.

A university's chief librarian is poisoned, police believe he may have been the wrong target and their fears are confirmed when they discover another victim. Professor T is summoned to help solve to help solve the crime, to the horror of Chief Inspector Rabet who is yet to be convinced by his controversial ways.

The chairwoman of the school's inspection team is murdered at home. At first sight, it looks like a robbery gone wrong but Professor T is convinced the school principal is somehow involved. Annelies and Daan confront Rabet over his increasing drink problem but agree not to tell the commissioner. Annelies meanwhile, opens up to Daan about her father's Alzheimer's.

The police investigate the disappearance of a first-year law student with several secrets to hide. Meanwhile, Professor T is visited by a call girl and make a special arrangement. Due to her erratic behaviour, Daan begins to suspect Annelies has a boyfriend but she soon puts him straight. Meanwhile Inspector Rabet's drink problem is getting worse and Annelies loses her temper.

A plastic surgeon is killed and the police are looking for a woman he spent the night with. Professor T believes she is innocent but Commissioner Flamant has forbidden her team to contact him for help. Professor T begins his own investigation, with serious consequences. Meanwhile, Annelies, agrees to go on a date with Daan and Professor T's mother becomes increasingly concerned about her son.

The call girl who visits Professor T is found dead in her apartment. The police believe she has committed suicide, but Professor T is not so sure and hides the fact that he knows the victim to stay on the investigation team. Inspector Rabet is back and he hasn't forgotten that Professor T betrayed him in front of his colleagues and Annelies and Daan are not speaking to each other.

15 years ago, Flamant solved a series of murders by a masked killer. Now an identical crime has been committed. Is it a copy-cat or did Flamant catch the wrong person? Rushed to hospital for surgery, Professor T helps Flamant from his sick bed. Annelies father shows up, completely disorientated and Annelies realises she needs to look for a proper long-term solution.

The kidnapping of a six-year-old boy shocks the team who endeavour to do everything they can to find him. However, Professor T, questions the innocence of his seemingly distraught parents. Professor T's Mother invites him to present at the opening of her art exhibition, a prospect he is dreading. Rabet finds himself subject to a formal enquiry following the miss-treatment of a guest inspector.

A man is accused of killing his boss, having been found standing over the body, Annelies and her investigation team are convinced he is guilty. However, following a presentation by Annelies to his students, Professor T has questions if they have the right man. Flamant finds herself in hot water, sparks fly between Daan and Annelies.

There is a hit on prominent businessman Johan Verhulst during an official happening. The shooter fails. A few days later a lot of blood is discovered in his upside down turned living-room, but there is no body. Verhulst has disappeared. Jasper deducts everything is staged by Verhulst himself, but then he is found dead after all.

A man is found by a dogwalker in a forest; his face severely torched, it seems he has been strangled to death, curiously he has the year 1991 carved into his chest. Days later a second victim is found also with a number carved into his chest - Does Antwerp have a serial killer? Where is Professor T when you need him?

With Daan fighting for his life in hospital, the search for the killer continues. Annelies meets with the widow of the third victim, urgently trying to find connections between the three murders. Unbeknownst to the team, he is much closer by than they could possibly imagine and has in fact already infiltrated the Department of Criminology.