Heidi, an orphan girl since she was 1 year old, has grown up under the care of her aunt Dete. However, just as she turns 5, Heidi is sent to live with her formidable grandfather Onji in the Swiss Alps when her aunt gets a housemaid job in Frankfurt. Heidi soon befriends a goatherd named Peter, and she is amazed with the beauty of the natural surroundings and explores her new home with visible satisfaction as Onji gets lost in his thoughts.