16 year old Lorenzo (played by a very young Jacques Perrin) finds the beautiful Aida (Claudia Cardinale) in front of his front door, carrying a suitcase, looking for a man named Marchiori, who has abandoned her. Knowing that the man she wants is his own brother, who has given her a false name, Lorenzo decides to help her, to right what his brother has done wrong. He puts her in a hotel and gives her money, and during all the time falls in love with her. Lorenzo's teacher warns Aida that what they both have been doing is not right, because Lorenzo has given her money which is not his. Aida leaves and looks for Piero (most likely her ex lover), who has promised to give her a job, but Piero turns her out. Piero's cousin seems keen to help her, but Aida soon finds that he has something else in mind. Lorenzo comes, picks up a fight with Piero's cousin, and Lorenzo and Aida flee to a beach.
There are some captivating moments, like when Aida meets Piero in a station, with Lorenzo following them, trying to hear what they are talking about. To prevent her to go with him, Lorenzo tells her that he knows where Marchiori is. Later we see Aida breaks down and tells Lorenzo about her past, that she has a son.
The story flows very well and we learns about Aida from Lorenzo's point of view. The scene on the beach is very beautiful, and it's when we see that Aida does love Lorenzo, even though only a little.