In the course of the lawsuit against the dubious building contractor Hans Woitek, a partner of the defendant crashes to death. Prosecutor Binz is convinced that this is murder. Apparently Karsten Tiedemann should be silenced in order not to bust the mafia structures in the industry. But the investigators find a new trail that leads to the Czech Republic. Just as the investigators are about to solve the case, prosecutor Binz and his family are threatened, so he appeals to investigator Ina Zimmermann to stop the investigation immediately.