A headless male body is recovered from the Spree, whose identity is difficult to establish. A little later, Nina Rubin is being followed by a young woman. Julie Bolshakov tells the detective that she witnessed a murder and asks Rubin for police protection. However, contact with Julie puts Rubin in a dilemma, because from now on she has to keep Karow out of the investigation so as not to endanger the young woman. Karow investigates the identity of the dead man, but senses more and more that his colleague is hiding things from him. Trust has been a thorny issue between the two from the start, and Rubin's behavior hurts Karow - especially since they've also become closer privately. All the more the old problem breaks out again. In her latest case, will Nina Rubin be able to free Julie from the clutches of her crime family?