Paul, a former concert pianist, lives in the picturesque town of Krems with his adopted son Rico. Since the accidental death of his wife Anna, he has been living alone with his son. When Paul falls in love with the beautiful Luisa, he starts playing the piano again. What Paul doesn't know is that Luisa is Rico's biological mother and has already made friends with the little boy, without knowing that Paul is Rico's adoptive father. When Paul finds out, he feels betrayed by Luisa and confronts her. The situation comes to a head and Luisa travels back to Italy. But Paul quickly realizes that he wants to give his adopted son the chance to get to know his biological mother. Together with Rico, he travels to Italy to see Luisa again. They have a heated argument there and don't realize that Rico is eavesdropping on them. When he learns that Paul is not his father, the little boy's world falls apart.
