Inspector Frank Thiel is looking forward to an exciting evening of football, Prof. Karl-Friedrich Boerne is fine-tuning his acceptance speech for the science prize and father Thiel is trying to find his inner balance while fishing at night when a foot stuck in a motorbike boot causes a stir. Prof. Boerne is alarmed: Hasn't he seen this foot with an extremely rare deformity before? The suspicion quickly becomes certain: his former classmate Susanne Clemens was apparently the victim of a crime. Their investigations lead Thiel and Prof. Boerne to the tennis club where Susanne last worked. Maybe it's no coincidence that there was a break-in here. For the young tennis talent Nadine Petri, the excitement comes at the worst possible time.
The big tennis tournament in a few days could be her international breakthrough. Her ambitious parents, Ilga and Walter Petri, don't tolerate any disruption to the training schedule. But Thiel is not impressed by that. The search for clues in Susanne's environment also leads the inspector to the "Wotan Wolves", a notorious rocker club with connections to organized crime.