The renowned psychiatrist Oswald Nys has a very strange hobby: he tortures prostitutes who are delivered to him by nightclub owner Bellon. However this goes terribly wrong and the illegal Akkim dies. Another victim of Nys, Sylvie Van Dijck, who is a coke addict, threatens to tell the whole world and phones Matti to make an appointment. But she doesn't show and a night later she is found dead. The only starting point Matti has, is the name Akkim. For some strange reason Sylvie visited her father, Eric Van Dijck, the night she was murdered. She hasn't made contact with him in years. Why now?