The book opens with Tex McCormick who is a happy 15-year-old who loves horses, his brother Mason, living in a small town and Jamie the girl next door. Tex is growing up mostly with Mason in a small country home. Their mother died years before and their father goes off for months at a time leaving Mace, a senior and a star basketball player and Tex at home. At the start of the book Tex comes home to find the two brothers' horses sold. Negrito, Tex's horse, was considered a friend to Tex. However Mason had to sell the horses to guarantee Tex and himself would have enough to eat over the winter. This action by Mason sets Tex against his brother for most of the book.
But the McCormick brothers are not alone. Living in the significantly larger ranch house next door (about 0.5 mi (0.80 km)) are the Collinses, the family includes Mason's best friend Bob, Tex's best friend Johnny and the younger sister who Tex loves, Jamie. The Collinses, however are forbidden to see Mason and Tex because the patriarch of the Collins family, Cole thinks they are a bad influence.
After a turn of events involving Tex and Mason's father, Tex runs away to the city with a family friend and eventually learns that just living life and staying with his brother is the best thing for him.