The following version of the book was used to create this study guide: Harmel, Kristin. The Forest of Vanishing Stars. Simon and Schuster, New York, NY 10015. 2021. Kindle AZW file.

When an old woman named Jerusza receives a divine message that she is to kidnap a 2-year-old girl from the home of her German parents, she feels she has no choice but to obey. She renames the girl Yona because of a dove-shaped birthmark on the child's wrist. She takes Yona into the forest where she teaches her to survive on the bounty of the forest. They slip into villages and towns to take the supplies they cannot get from the forest, including clothes and books. Jerusza teaches Yona several languages, religion, and traditional subjects she would have learned in school. Yona develops a sixth sense for life in the forest and detecting danger. Jerusza warns that interacting with people is dangerous and teaches Yona multiple ways to kill someone. Jerusza issues veiled threats and warnings that make Yona wary even while she longs for a friend.

Jerusza grows frail and dies, issuing final warnings with her last breath, and Yona settles into life completely alone. She wonders how much of Jerusza's information is true but remains in the forest with very limited human contact. One day she finds a little girl who is alone and barely alive. Yona cares for the little girl and finds her parents. She heals the father's gunshot wound. She learns that the Germans have begun killing Jews, which is why this family ran into the forest. Yona does not remain with this small family but finds their bodies a short time later. When she comes upon another group of Jewish refugees, Yona is determined to keep them safe. The group's leader is Aleksander, and he recognizes the value Yona brings to the group. She teaches them to fish, forage, and hide their presence from the Germans who are constantly searching the forest. She depends on her sixth sense about danger to keep them moving at opportune times. She and Aleksander settle in as a couple, making it to the first winter. When another group of refugees arrive led by a man named Zus, Yona immediately agrees that they should join forces. The combined group has two dozen people. Aleksander is angry that she made that decision without consulting him. He fears there will not be enough food. Yona believes they have a responsibility to help each other.

When Yona discovers Aleksander having sex with another woman in the group, she quickly packs and leaves. She travels across the region, ending up in a small town with a heavy German soldier presence. She helps a nun who is trying to save a little girl with a gunshot wound. Later, this nun and seven others are about to be killed by the Germans in retaliation for a recent attack. Yona recognizes one of the officers as her father, Siegfried. He recognizes her because she has one blue eye and one green, and she bears the distinctive dove-shaped birthmark. Yona discovers that Siegfried is as evil as Jerusza predicted he would be. She learns the Germans are planning to search the forest and returns to warn Aleksander, Zus, and the others. They continue to survive, though the conditions are sometimes terrible.

Though Yona thinks of this group as her family, she never feels that she fits in with them. The group continues to grow in spite of a few dying in various ways. When it becomes clear they will not survive through another winter, they attack a German supply truck, hauling back winter clothes, guns, and food. The relationship between Zus and Yona grows closer, tempered only by Zus's grief over his dead wife and daughter. On the night Zus realizes he needs to open his heart again, Siegfried finds them. He is alone, having wandered through the forest in rage over Yona's departure. In his raving, he reveals that he learned Yona's mother was a Jewess who hid it from him. He shoots at Zus, but Yona jumps in the way. As she lies bleeding on the ground, she manages to kill Siegfried, using one of the lessons Jerusza taught her years earlier. Zus runs back to camp with her.

The final chapter gives an overview of the years following the shooting incident. The war ends, leaving the Jewish people decimated. Yona and Zus remain together until Zus dies at 89 years old. They have two children who grow up and move away but return often to visit. The children are with Yona when she dies in 2019 at age 100, just as Jerusza had known she would.