Sixteen-year-old Riley Meemick is one of the world's last free girls. When Riley was born, her mother escaped the Breeders, the group of doctors using cruel experiments to bolster the dwindling human race. Her parents do everything possible to keep her from their clutches - moving from one desolate farm after another to escape the Breeders' long reach. The Breeders control everything and they're hunting Riley. When the local Sheriff abducts the adult members of her family, Riley and her brother Ethan are left to starve. Then Clay arrives, the handsome gunslinger who seems determined to help to make up for past sins. As Riley's affection for Clay grows she wonders can she trust Clay with her secret and risk her freedom? The three embark on a journey across the scarred remains of New Mexico. When Riley is forced into the Breeder's hospital, she learns the horrible fate of her mother - a fate she'll share unless she can find a way out.