The inconspicuous greengrocer's daughter Maria had to watch as the adored Italian Pietro broke her best friend's heart. Dressed up as a vamp, the vengeful Maria now sets a cunning trap for the attractive Papagallo. Maria is the daughter of a small German fruit and vegetable dealer, Pietro is the son of a large Italian fruit and vegetable dealer. Both live in Munich and both meet every morning at six o'clock in the Grossmarkthalle. Maria looks inconspicuous, while Pietro looks extremely attractive. Maria is hardly interested in men, whereas Pietro is interested in all girls. Maria doesn't care until Pietro first seduces Maria's best friend and then leaves her unhappy. Now Maria starts a campaign of revenge against the light-footed Casanova, in the name of her best friend and in the name of all the girls who have been seduced by Pietro. Maria lures Pietro, who is now madly in love with her, to his native Italy, where Pietro, blinded by love and jealousy, proposes to Maria.

Customs officers Katti and Wolfgang are so deeply in love with each other that they are barely aware of their surroundings. But after the wedding reception, there's nothing but trouble.