At the beginning of the school year, teacher Heike Fuchs does not show up in her class. When the police find her in her apartment, it quickly becomes clear that Heike Fuchs was drowned in her indoor fountain weeks ago. At the scene of the crime, Lena Odenthal notices a young black girl who obviously wanted to enter the apartment, but immediately ran away when she saw the police. When Lena meets this girl again at school, it strengthens her suspicion that the student is Eshe Stegerhad something important to say about Mrs. Fuchs. But Eshe stubbornly remains silent and is supported in this by her mother Dafina and her stepfather Enno. Nevertheless, there seems to be a connection, because Heike Fuchs was a visitor at the German-African meeting center, in which the Stegers also play a role. Only very rarely and only because of an art project, assures the manager Regula Großmann. Nevertheless, Lena remains suspicious.