In the winter of 1865, seven-year-old Ruth Ann is sent west by her enslaved parents to escape being sold away. With only her faithful dog, Buttons, beside her, she follows her father's final instruction: keep the setting sun ahead and walk toward freedom.
Rescued by a kindly carpenter and his daughter, Ruth Ann begins a new life as Minnie, growing up along the expanding transcontinental railroad. Surrounded by friendship and a loving new family, she never forgets the parents she left behind.