Shirley Temple, in a role that seems custom-made for her, portrays the spirited young heroine of the popular children's novel, giving her rich emotional depth and infinite charm. When her aunt tires of caring for her, orphan Heidi is taken into the Swiss mountains to live with her gruff grandfather (Jean Hersholt), a hermit who comes to adore her. But the aunt returns to steal Heidi away, selling her to a family whose invalid daughter (Marcia Mae Jones) needs a companion. Bullied by an evil governess (Mary Nash), Heidi still charms the entire household and never stops trying to return to her beloved grandfather.