In a sunny district of Naples where everyone knows each other, Mario and Lino, two inseparable friends, live day by day in the monotony of neighborhood life until their fraternal friendship is put to the test.

Filumena has lived for years with a wealthy pastry chef. She forces him to marry her, but he soon asks to annul the marriage. She then reveals that one of her children is his, making him obsessed to know which one.