The young architect Hannelore becomes part of the all-male brigade Fröhlich whose members are supposed to build houses at the Strausberger Platz in Berlin. The brigade men drink a lot of beer and are less than thrilled about the new girl. Hanne is the only one who is absolutely delighted with Hannelore. When he starts a drunken fight on May Day, he is arrested and accused of armed robbery. Hannelore immediately convinces the other men in the brigade to help Hanne.
Germany 1932, constant fights between Communists and Nazis tear the country apart. When a Communist is found dead, the police accuses another Communist being his murderer. But the Communist youth group follows another trail - the murderer left a characteristic boot print at the scene of the crime.