"The beautiful Mona", that's what the people in the village say when they talk about Mona Seitz. A vital, fun-loving woman who has always been at the front of the party at the soccer club home since she was young. After one such celebration, Mona's chariot is found at the foot of a cliff, no doubt pushed off by another chariot. The victim's blood is found in the car, drag marks show that the body was dragged into Lake Constance. Klara Blum and Kai Perlmann have two main suspects: Fritz Schönborn, formerly the town's football god, is now on a steady downward curve. And Christian Seitz, Mona's husband, who moved to her home town because of her, but never felt at home there. Christian Seitz has the village, especially Mona's brother Stefan Mader, against him.
He insists that despite their differences, he and his wife were a happy couple. But did he know that Mona was having an affair with her childhood sweetheart Fritz Schönborn? Does he know the other, dark side of beautiful Mona? It's up to Klara Blum to unravel the web of love, contempt and lies.