A policewoman from Berlin who testified against an Arab clan boss is starting a new life in Passau with her daughter under a new identity and with the support of witness protection. The policewoman, who until recently was a group leader in the Mobile Task Force (MEK), now calls herself Frederike Bader, her daughter Mia Bader. In Passau, she meets private detective Ferdinand Zankl. In a supermarket, she rescues him from a violent confrontation with a shoplifter.
Private detective Ferdinand Zankl is arrested by the Passau police on suspicion of murder. He is suspected of having killed his ex-girlfriend, an animal shelter manager.
Between 1924 and 1934, six children grow up in an apartment building in the Munich suburbs. Among them is the rather inconspicuous and melancholy Leo Knie, who has been in love with the pretty Marilli Kosemund since early childhood. Marilli is not averse to the young man's advances, but she wants to be conquered. But that is exactly what shy Leo finds difficult. So he escapes into harmless dancing with his buddies, pursues other girls - rather unsuccessfully - and resigns himself to his predetermined fate.
