Harry Lund, 19, works in a glass and porcelain warehouse. Nearby, in a vegetable warehouse, works Monika, 17, a cheerful and happy girl. After meeting Harry in a café, they fall in love.
Monika argues with her father and leaves home. Harry quits his job because he has a falling out with his boss. With nothing tying them to the city, they take Harry's small boat and leave to spend some time alone.

A Summer with Monika condenses three months of a romantic relationship that has a bright beginning, a passionate climax, and a decadent ending. The film brings into play two ways of looking at life and love: his, who dreams of seducing and making the girl he is with happy, and hers, much more fanciful, who conceives and compares her existence to Hollywood melodramas.

Synopsis written by the Young Programmers group