Hacienda de Nuestra Señora de la Purísima Concepción (La Purísima) is owned by Don Héctor Rocha y Villareal, a powerful rancher with a love for horses. John Grady and Rawlins watch him leave to hunt with his dogs and realize that he’s bringing back wild colts that live on the ranch’s land. The boys decide to break the colts themselves, betting that they can get all 16 to a rideable state in four days.

The boys get permission and begin, and the novel describes the process of breaking the horses in procedural, minute detail interspersed with John Grady and Rawlins’s sarcastic banter. The vaqueros observe them, and the proceedings take on the air of a festival as more people come to watch them train and ride the wild horses. Rawlins challenges John Grady to tame one horse in particular, a rare kind of dun-colored horse called a grullo. By midweek, John Grady rides some of the horses into the country while Rawlins works with the others in the pen. On one of these rides, he’s passed by Alejandra, Don Héctor’s daughter, on her fine Arabian horse.

Their work impresses the gerente (ranch boss), so John Grady and Rawlins are sent into the mountains to bring down more wild horses.