The well-known Berlin radio presenter Nico Lohmann (Florian Panzner) and his pregnant girlfriend Anne (Klara Manzel) were to fall victim to a letter bomb. She misses them both, and a young boy dies playing ball in the stairwell at the wrong moment. Ritter (Dominic Raacke) and Stark (Boris Aljinovic) first research the callers of "Nico's Night" and come across Petra Piwek (Karina Plachetka), who left her violent husband on Nico's advice. Heiner Piwek (Andreas Guenther) follows Nico from now on. But Ritter and Stark also find inconsistencies in Lohmann's CV: the former competitive swimmer, whom his father Hans Lohmann (Hans Uwe Bauer) trained with all his might, caused a serious car accident five years ago and then ended his sports career.
In search of a motive, the inspectors also investigate Nico's girlfriend Henriette (Julia Koschitz), from whom Nico broke up at the time. The victim of the accident, Ulrich Kastner (Peter Schneider), whose wife and little daughter died, is still convinced today that his wife did not cause the accident. At that time, detective Karl Vornier (Andreas Leupold) was investigating the case. He confirms that the accident was never properly clarified - The "Tatort: Big Black Bird" is a production of Ziegler Film GmbH & Co KG (Regina Ziegler) on behalf of Rundfunk Berlin-Brandenburg for Das Erste