Inspector Peter Heiland has been transferred from Stuttgart to the Homicide Division in Berlin: the clumsy detective first has to find his feet in his hectic metropolis. But there is hardly any time for him to do so, because a vicious sniper has already killed four people, and the police are still completely baffled. Supt Ron Wischnewski can't stand Heiland, but he is from Swabia, as were three of the victims, and it seems likely that he can now contribute to the investigation, so Wischnewski grits his teeth and appoints him to the "Special Sniper Squad".
Sascha Gräter has developed a taste for killing. He has never properly come to terms with the humiliations inflicted upon him during his childhood, and now here attempts to find release through violence. The only person who has began to suspect in so far is his landlady, Cordelia Meinert. This attractive, lonely woman feels torn: on the one hand she is afraid of the secretive, good-looking man who is several years younger than her and drives around with a gun in the back of his car -but on the other hand she does feel sexually attracted to him... and Sascha takes whatever he wants. But when he notices that Cornelia seems to know too much about him, he begins to fear that she will betray him...
Peter Heiland has found two friends in Berlin, a colleague in the police department called Hanna and a juggler by the name of Manuel. Now he is filled with enthusiasm and set about reinvestigating their cases. And soon he succeeds in finding ammunition of the sort used to kill the first victim in the cellar of Sonja Michel, the flatmate of the deceased. But this woman is in a wheelchair and could hardly be suspected of being a sniper -- and how horror at the fact that the number of victims is mounting seems convincingly genuine. Hardly has Heiland left the house when she confronted her nephew Sascha, whose she brought up A after his mother's death. He doesn't show any sign of regret. When Sonja Michel kills herself, overcome by guilt because she prompted her nephew to commit the first mruder, Sascha decides that Peter Heiland is to blame and sets out to get revenge. After a visit to the Opera with Hanna, Heiland only just manages to escape an attempt on his life. At least now he knows that the killer is after him. He views the sniper to his home town, Riedlingen. Heiland has come to tell Sonja Michel’s mother, who lives in an old people's home, about her daughter’s death. But the old lady has Alzheimer's and confuses Heiland with her grandson Sascha, who was here just a short time ago. Heiland put two and two together and realises that the man in question is a former schoolmate, Sascha Gräter. He remembers that the shy boy was accused of rape and treated badly by his gang -- and then Sascha from the area.
Now Heiland also knows who else Sascha has his sights on for his campaign of revenge. And when Heiland’s grandfather Henry reveals to him that Sascha is his cousin, the game of cat and mouse reaches a climax on the huge rocks overlooking the Danube.