Klara Blum is on the hunt for the arms dealer Meiners. He is suspected of having shot a young policewoman. The Swiss colleagues around Reto Flückiger from the Thurgau canton police are also interested in Meiners, because he is a liaison to the Swiss arms dealer Hutter. During the transfer of the suspect to Germany, Klara and her Swiss colleague are ambushed. Apparently, the pursuers were given a tip from the ranks of the police. Separated from the escort team, without a car and being pursued by Hutter's people, Klara and Reto Flückiger try to get their suspect to safety. While Perlmann works in Konstanz to track down the mole in the ranks of the police, not only the inspectors but also their prisoner become the hunted.
Because in the first confrontation with their pursuers it turns out that they don't want to free Meiners, but want to kill them. While Klara Blum protects the life of her prisoner, she is suddenly no longer sure whether she caught the policewoman killer in the arms dealer or not.