Switzerland in the 1950s: Electricity consumption is rising steadily. Two officials are commissioned by the city to convince the inhabitants of the Gettlichtal to leave voluntarily so that dams and reservoirs can be built. But the mountain farmer Marie, who has spent her entire life here, finds it difficult to leave the valley.
Heidi, is an eight-year-old Swiss orphan who is given by her aunt to her mountain-dwelling grandfather. She is then stolen back by her aunt from her grandfather to live in the wealthy Sesemann household in Frankfurt, Germany as a companion to Klara, a sheltered, disabled girl in a wheelchair. Heidi is unhappy but makes the best of the situation, always longing for her grandfather.