Heidi (Shirley Temple) is an 8-year-old orphan living the last six years with her sourpuss Aunt Dete (Mady Christians). The aunt uses as an excuse that she found housekeeping work in Frankfurt to dump Heidi on her reclusive Swiss Alps residing misanthropic elderly grandfather Adolph Kramer (Jean Hersholt). Gramps stopped talking to the villagers of Dorfli when they sided with his son, Heidi’s father, when the boy married someone his father disapproved and then threw his son out. Soon the cheerful Heidi melts her crusty embittered grandfather’s heart and the two become inseparable, but the avaricious Aunt Dete returns and steals Heidi away to sell her into servitude in Frankfurt. Heidi ends up working at the home of a wealthy businessman, Herr Sesemann (Sidney Blackmer), who is hardly ever home. When Heidi befriends Sesemann’s crippled daughter Klara (Marcia Mae Jones) and teaches her to walk, he fires the evil housekeeper Fraulein Rottenmeier (Mary Nash) who kept Klara a crippled so that she can possibly marry her widowed boss because of her value to his daughter. Meanwhile gramps walks on foot to Frankfurt and rescues Heidi from being sold to gypsies by Fraulein Rottenmeier.