In 1853 young Boone Tyler is thrust alone into the rapidly changing and dangerous environment west of the Mississippi. Was his white mother killed by his Kiowa father? His mother refused to let Kae-Gon into Boone's life, but he told Lynelle he'd come for Boone when he was twelve. She swore she'd rather kill Kae-Gon than see Boone live in a world under constant threat. She made Boone swear to stay white, even taught him Shakespeare to help center him in her world in eastern Kansas. After her death, Boone seeks out his grandfather, an army general, to help him kill his father. He quickly learns that many in the white world only see him as Indian. On his adventures alone in the wilds of the western territories, Boone is often saved by the mysterious voice in his head that he thinks is his dead twin brother. Sam's voice, and the symbols he becomes obsessed with, remind him that he's more than just a half-white son and to learn more of his father's world before killing him. Events keep tangling with Boone's desire for revenge for Lynelle's death, including a wife, a cattle drive, thieves, Civil War, and people who continue to see him as Kiowa, not white. By 1874 he comes to understand the meaning of being "half-breed," but is Sam's voice enough to save their father's life?