Professor T. - Season 4

The detectives are confronted with a brutal sight when they find the body of a young woman. She has been shot in the face through the door peephole, making identification almost impossible. Karoline Gerber, the girlfriend of the deceased, is shocked when she enters her apartment. It later transpires that Karoline is a witness in the murder trial against drug lord Ezequiel Morales.

Sophia Gruber had big plans when she handed over the company to her son and devoted herself to art. But now the millionaire is dead, lying among the stinking garbage in the landfill. Hans Gruber is shocked. Sophia's son, the sole heir to the Gruber Zünder company, is no stranger to Professor T. At boarding school, they shared a room and fantasized about murdering their mothers.

Kai Schilling is dead. The Cologne tabloid journalist not only had star soccer player Lukas Pommer in his sights recently, but was also the inventor of the "murderous professor." Well-known and unpopular throughout the city for his controversial articles, the detectives are faced with a long list of possible perpetrators.

Christina has been shot. The evidence at the scene makes it clear to the stunned detectives: she must have known the perpetrator! It must have been someone she trusted. Daniel tries to get a name out of her in the ambulance, but Christina's last words before she is wheeled into surgery and placed in an induced coma are solely directed at T.