Heidi lives with Alp-Öhi n the Swiss Alps in the summer, where she helps Peter tend the goats. In winter, she stays in the village and attends school. One day, a letter arrives from Heidi's German friend, Klara Sesemann, announcing her visit. Klara indeed appears the next summer along with her grandmother and the prim governess Miss Rottenmeyer. Klara is quickly convinced to stay with Heidi, but Peter becomes resentful that Heidi now spends so little time with him...

Heidi, a young orphan girl living with her aunt in Frankfurt, is forced to move to the Swiss Alps to live with her ornery grandfather. At first, he resents her presence, but, after a short while, Heidi manages to pierce his gruff exterior, and the two become close. She also befriends a young shepherd named Peter. After three years, Heidi's aunt arrives and demands Heidi's return to Frankfurt.

At the age of three, little Wolfgang has lost his parents. Since then his uncle Eduard raises the boy. As a former concertmaster Eduard has recognized how gifted his nephew is and the boy learns the hard way. The 6-year-old must practice daily 6 hours at the piano and already impresses at famous music parties. When Eduard Fabricius breaks a leg after a concert in Lucerne and must go to the hospital, he can be persuaded by a pediatrician to grant some carefree vacation weeks in a manor for Wolfgang. The manor belongs to the young widow Elisabeth who soon grows very fond of the little boy. Wolfgang makes friends with 11-year-old Heidi and Jöggi, a boy his age who first saw a rival in him...