Art student Ulla lies to her older sister Ilse, claiming to be posing for sculptor Professor Viktor Arnim. To confront him, Ilse visits him that very evening. In her excitement, she forgets her handbag, which the professor immediately notices. Ilse clearly doesn't dislike Viktor and no longer wants to appear as the strict sister. So she lies to Viktor and his friend Philipp Geiger, who is also present, telling him that her handbag was stolen by a man named Meier. Viktor and Philipp immediately offer to retrieve it. Sure enough, the famous boxer Willi Meier lives in the neighborhood. Viktor and Philipp also find a woman's handbag in his apartment, which they secretly take with them.