Stefan Aldinger, one of the two operators of the colourful, diverse Stuttgart art complex Wagenhallen, is found dead. His wife Elena seems completely broken by the news. But she is one of the suspects, because the Aldinger couple had had a heated argument the night before the murder, and not for the first time. Jealous kickboxer Elena is known not to shy away from physical arguments. On the other hand, the murder happened in the midst of passionate political struggles for the preservation of the Wagenhallen, because the ambitiousInvestor Walter Rühle wants to build a high-quality residential project on the site. He has many local politicians on his side and also the art museum, namely the curator Julian Siebert, to whom he has promised his top-class painting collection.
When Rühle is arrested, he admits that he was able to "convince" Stefan Aldinger shortly before his death with the help of lucrative promises. The investor seems relieved, but with this statement he is incriminating Aldinger's partner Timo Holzmann, who does not want to give up the art area at any price.