Sarah Cisneros believer her sixteen-year-old twin sons, Adam and Benji, are far too young and far too innocent to participate in the ranch's upcoming cattle drive. But the boys are insistent and are eager to build the legacy of Dos Encinos. This will be one last adventure before they head off to college. Adam sustains serious injuries during a stampede while on the ride. As he recuperates in the small central Texas village of Comanche, he becomes enamored with the innkeeper's daughter, Martha Taylor. Adam and Martha pledge to wait for each other as Adam enters medical school in Fort Worth, Texas. Meanwhile, Benji pursues his dreams of becoming an architect. After graduation from medical school, in spite of more enticing and lucrative opportunities to settle in an urban community, Adam returns to Comanche, re-unites with Martha, and starts his medical practice. He doesn't realize the hostilities and personal threats he would face in bringing new concepts of medical treatment to a community served only by charlatans and untrained doctors. Adam must rely on his heritage of strength from the pioneer cattlemen of south Texas--his Dos Encinos legacy--to guide him through the strife he faces.