Happier than ever, Per believes that life is like a fairly tale. He dreams of the day when he will own a mansion and more land and livestock. Restless, he always works. One day, Ole and Store-Hans find a swamp brimming with ducks, and they excitedly tell their father about it. One Sunday, Per goes with Store-Hans to see the ducks. On the way home, Per makes a startling discovery. He finds a stake in the grass on Tonseten's land. However, the name on the marker is O'Hara, not Tonseten. After the initial shock, Per decides to search Hans's land. Sure enough, he finds another stake. The name on the stake is Joe Gill. Tears come to Per's eyes, and he feels disheartened.
Per knows that other people, or trolls, placed the stakes on the land, and he decides not to tell anyone about what he has found. He looks for a stake on his land but does not find one. He removes the stakes on his neighbors' land and fills the holes that are left behind. Beret, however, can sense that something troubles Per. One day, she finds the stakes in the barn. Later, she sees Per chopping up the stakes and burning them. She realizes that he must be meddling with other people's landmarks—something considered a heinous crime in Norway.
Per sleeps well that night, but Beret cannot sleep because she realizes that Per has committed a sin. During the next few weeks, Per's temper makes him hard to approach. He worries about what will happen when the trolls return to claim the land. Beret finds Per difficult to live with, and her depression grows. She often looks at the lonesome prairie, wondering how human beings can live here.
One day, a large caravan arrives unexpectedly. These newcomers do not approach the Norwegian settlers, however, so Per and Tonseten think that they must be unfriendly. They go out to meet the caravan. Because Per does not know English, Tonseten speaks to them. Tonseten tells Per that the newcomers are Irishmen who claim that the land belongs to them. Per realizes that these people are the ones who placed the stakes in the land.
Per and Tonseten return to their homes. Per feels convinced that the Irish have no legitimate claim to the land because they did not file an official land claim, as the Norwegians have. At home, Per is in a good mood for the first time since he found the stakes. The next morning, Per tells the Solums about the Irish. He asks for their help as translators because both Henry and Sam speak English well. Per then goes to Hans's place, and explains to Hans that the Norwegians must show the Irish their deeds to prove that the land belongs to them, not to the Irish. Per leads Hans, Tonseten, and the Solums over to the Irish camp, explaining his plans. Per tells them that they should ask to see the newcomers' deeds and their stakes.
The Irish do not greet the Norwegians warmly. The Irish cannot produce their deeds or find their stakes, and they accuse the Norwegians of destroying their landmarks. A fight brews between the Irish and the Norwegians. The massively built Hans punches the apparent leader of the Irish and throws him in a wagon. The Irish back down from the fight, and they decide to settle on the other side of the creek.