Set in nineteenth-century Nebraska during the era of homesteading and range wars, the story follows eleven-year-old Nathaniel (Nate) Peale, whose life on his family's frontier farm is shattered by a catastrophic accident. Nate lives with his father, Gabriel (Pa), and his mother, Mary Eve (Ma), a skilled tinker who secretly repairs clocks and tools for the community, though customers assume Pa does the work because people do not accept women performing what they consider men's labor.
One morning, Ma warns that a storm is approaching, and Nate and his parents rush to bring in hay. As the horses spook, the wagon jolts. Nate, standing on its edge trying to free a jammed pitchfork, loses his footing, and his leg slides into the turning wheel, shattering the bones. He drifts in and out of consciousness for over a week while Doc Kelly, a physician in town, sets the leg using traction. Doc Kelly delivers grim news: The leg will never mend properly. At best, the bones may grow together enough for Nate to walk, but walking will always be difficult.
The injury compounds an already desperate situation. Two years earlier, locusts destroyed the family's farm in Goshen, Illinois, forcing Pa to surrender the land to the bank. They relocated to Chicago, where Nate worked in factories instead of attending school. During that time, Nate's infant sister, Missy, choked on bread and died while in a neighbor's care, a trauma that haunts both parents. Ma insisted on a wood house in Nebraska, so Pa sold everything to buy lumber and ship the family west. They built their household through Ma's tinker trade, bartering repairs for furniture, seed, and food.
With Nate bedridden, Pa loses most of the hay to the storm, and neighboring cattle break through a fence and destroy the north corn field. Pa works from before dawn to sundown and cannot look at Nate directly. Ma tells Nate that Pa watches him from the doorway at night and likely blames himself for the accident. Nate tries to learn tinkering but cannot reassemble the old clock Ma gives him.
Pa then heads to town and returns with John Worth, an orphan boy from an orphan train, a program that transports homeless city children to rural families. Ma tearfully insists Nate is their only son and that John is merely a farmhand. John arrives as a city boy covered in mosquito bites who will not meet Nate's eyes. Ma banishes him to sleep in the lean-to, a wood storage shed attached to the house, and at night Nate hears John crying through the wall.
Determined not to be replaced, Nate begins rebuilding strength in his wasted leg. Ma sends him to school for the first time, where he is placed with the youngest children and humiliated by his inability to read or do arithmetic. The children mock him as "Wood" for his family's lumber house and laugh at his hobbling gait. Nate observes bitter hostility between homesteader and rancher children, especially between Horace Danver and Trevor Gantry, whose families feud over land and the suspicious drowning death of Horace's brother Calvin on Gantry property.
At home, Pa remains distant. One night, after drinking with neighboring rancher Seth Clemson, Pa confesses the guilt consuming him: for losing the farm in Goshen, for dragging the family to Chicago where Missy died, and for pushing to bring in the hay during the storm that broke Nate's leg. Ma insists he did not cause these tragedies, but Pa storms off. Nate's anger deepens too. During a church service, he prays for God to suffer as he has suffered. Overwhelmed by frustration at school and his injured leg, he throws his reading primer out the window and buries himself in bed.
A turning point comes through an unexpected friendship. A Greek immigrant classmate named Anemone Cordimas leaves a peeled orange on Nate's school bench and lends him a book of Greek myths. He devours the stories nightly, reading aloud. Through the wall, John, who has been teaching himself to read with Nate's discarded primer, overhears and asks to hear more. The two boys begin reading myths together through the lean-to wall. Nate recognizes that John's situation mirrors his own: Both feel stupid in unfamiliar environments, both carry fear, and both bear deep pain.
One night, fence cutters snip through the barbed wire and Clemson cattle stampede through the Peale cornfield, destroying crops the family desperately needs. Nate directs John to run a mile in the dark to fetch Mr. Clemson. Afterward, Nate makes John cinnamon tea to calm his shaking and shares that he once felt the same terror navigating city streets at night. The mutual admission of fear builds a tentative bond.
The fragile connection ruptures and reforms through a violent fight. Riding through the ruined cornfield, Nate laughs at a private fantasy; John, working nearby, assumes Nate is mocking him and attacks. Nate leaps from the horse and beats John bloody before stopping himself. When the misunderstanding clears, both boys laugh at the absurdity of their hatred and bond over shared losses on the walk home. Inside, Ma sees John's battered face and assumes he attacked Nate, throwing him into the lean-to and declaring he will be gone by morning. Nate shouts that he was the one who hit John. Stunned, Ma apologizes. John breaks down sobbing, insisting he comes from a good family. Ma holds him as he cries, and for the first time, Nate hopes John does not have to leave.
Prospects shift when Pa arranges for Clemson to pay for the ruined crops in cattle. Pa invites Nate to help build a cattle pen, the first real farm task offered to him since his injury. While cutting clay bricks by the river, John confides the full story of his family's death in a tenement fire: A man's pipe started the blaze, the fire escape collapsed, and John's parents, brother, and three sisters perished while John was out gambling behind a shop, having lied to his mother about his whereabouts. The guilt of surviving on that lie haunts him. He proposes a trade: He will teach Nate quick arithmetic if Nate teaches him reading and history, aiming to earn a diploma and a bank job in New York. He states bluntly that Pa told him he will never inherit the land. Nate acknowledges the unfairness but agrees to help.
The climax arrives when Nate spots a figure with shears heading for the Clemson fence line and recognizes the torn blue shirt of Horace Danver. Nate and John ride together on Belle, the family horse, intercept Horace, and seize his shears. Realizing Horace has recruited other boys to cut fences while the adults attend a town meeting, they gallop into town and burst into the church shouting warnings. They then ride to the unprotected farm of the Widow Kerensky and scare off another young fence cutter before Nate's leg gives out.
Pa arrives home saluting both boys for stopping a range war. Nearly a dozen young fence cutters are caught. Mr. Danver, Horace's father, visits to apologize and offers Horace's labor during harvest, confessing he cannot lose another son. Pa looks from Nate to John and replies that he knows the feeling. Pa builds Nate a crutch with a flip-down seat, and the three of them build the new cattle fence together. Nate reads Pa's words as acknowledgment that John is now part of the family. He reflects that his leg will never be whole, Ma will never hold Missy again, and John cannot see his family until heaven, but together they will make do, and what they have is pretty good.