Popular Tune.

The story is set in Berlin at the beginning of the 20th century. The members of a singing group live in poor conditions in a dilapidated building. When the manager of the property is murdered, Peter and Paul, both members of the singing group, become suspects in the murder. When they return from a performance, the police are waiting for them to take them in for questioning. Since Paul is the most likely perpetrator according to the investigation, he is arrested immediately.