The novel begins as Dete hikes to Dörfli from her village of Maienfeld. Dete is taking her niece Heidi to live with her grandfather, whom everyone in the village calls “Uncle Alp,” because she can no longer care for the young girl and continue to work. Heidi is wearing all her clothes and becomes very hot on the trek up the mountain, but the scenery is beautiful.

Dete’s friend Barbel stops her and asks why she is taking Heidi to Grandfather’s since everyone in the village fears him. “Nobody really knows what’s the matter with that old man, but he won’t have anything to do with anybody, and he hasn’t set foot in a church for years” (3). Dete explains that her previous employers offered her a job at a hotel in Frankfurt, and she must hand over Heidi’s care to accept the job. Barbel asks Dete to explain Grandfather’s history in hopes of understanding why he is such a grumpy hermit. Dete explains that Grandfather’s younger brother was irresponsible and drank too much. He disgraced the family and his parents died of grief. Grandfather left home to join the army to escape the pain, married, and had one son named Tobias.