The inhabitants of Vienna line the streets to salute the soldiers who go to the war. The butcher and widower Franz Xaver Wamperl succeeds to enroll himself in the army, and so does his son Ferdl, who becomes a platoon leader. Ferdl is a womanizer, who at the same time has three fiancées in Vienna: Franzi, Resl and Poldi. All three girls remain faithful to him, when he's away at the front, and all of them send passionate love-letters to him. On May Day both Ferdl and his father Franz are back in Vienna on a short leave. They are sitting in an open-air café with another soldier, when suddenly Poldi and Franzi turn up at the same time. When the two women find out that Ferdl has a romance with both of them, they start to weep and quarrel. Ferdl tries to escape, but land in a fight between Franzi and Resl.