Astri is the older daughter of a family. Her father is the younger twin and works the land owned by his older twin. Astri's mother dies soon after giving birth to Astri's younger sister, Greta. Her father soon leaves for America and is never heard from again. Astri and Greta go to live with her aunt, uncle, and cousins. Astri's aunt is cruel, putting everything she can toward the futures of her daughters at the expense of everything else. One day, a cruel man arrives and pays Astri's aunt two coins and a large piece of meat in exchange for Astri.

The mean man's name is Svaalberd. He is a goatherd and Astri's life in his house is difficult. She tries to find a way to run away. When she makes Swaalberd very angry, he locks her in the storehouse. There, she finds a girl who doesn't speak and spends all her time spinning wonderful yarn. She's a strange girl and Astri never learns the girl's name and calls her Spinning Girl. She later discovers that Spinning Girl is actually Astri's twin sister, abandoned as a toddler because of a disease.

Astri does manage to escape and takes the Spinning Girl with her along with the treasure hoarded by Svaalberd. She has to chop off two of Svaalberd's fingers in order to escape. She knows that Svaalberd will now demand another girl to be his servant and Astri rushes to find Greta before he can take her. She and Spinning Girl arrive in time to run away with Greta just before Astri's aunt hands her over to Svaalberd.

Astri, Spinning Girl, and Greta continue their journey. Astri plans to catch a boat to America though there are obstacles in the way. They need money to buy supplies. Astri and Greta backtrack in the hope of finding Svaalberd's treasure. They find the sack and find that Svaalberd is nearby, dying. After they cover his body and hold a funeral service, Astri and Greta take the bag containing Svaalberd's treasure.

They arrive in a village and discover that the “treasure” is almost worthless. Astri and Greta spend almost all the money on a room for the night and a meal. Astri decides she won't return for Spinning Girl. Instead, Astri and Greta make their way to the ocean where they see the boat headed for America. They lie and steal to get aboard. Once on the ship, Astri is soon so seasick that she can do nothing for days. When she's recovered, a disease runs through the crew. Greta is soon sick and Astri slips into a dream.

In the dream, Astri recalls details about her past. She recalls leaving her sister with a troll. Astri dreams she takes a flask from the troll's castle and begins to climb a mountain. She meets a man who identifies himself as her Lord, another who identifies himself as the Devil, and a third who identifies himself as Death. Astri pleads for Greta's life. Death says that any time he sits at the head of a person, their death is sealed. If he's seated at their feet, the outcome is not certain.

When Astri wakes, Death is dozing at Greta's head. She has Greta turned so that her feet are pointed toward Death. Death is upset that he's been tricked and plans to take Astri instead. Astri asks permission to recite the Lord's Prayer first, and Death agrees. She falls asleep before completing the prayer and knows that she'll have to be careful not to ever complete the prayer.

As the ship nears America, Astri agrees to become a maid in the home of a young minister and his wife. Greta is taken in by a blacksmith who lost his wife and children during the trip. Astri knows she should be happy for herself and her sister, but she isn't able to find that happiness.

Throughout the story, Astri compares her situation to various fairy tales. She imagines that she is similar to the heroines in the fairy tales. She comes to realize that there are explanations for the various events.