Alex is preparing to make another trip into his father's computer when Cleo accidentally touches the screen and emerges amid a battle between the Nez Perce and Blackfoot Indians. Traveling into a myth is miraculous enough, but Cleo is amazed to discover that she can walk in the Alterworld. As Seeloo, daughter of a Nez Perce chief, Cleo also discovers that both great love and tremendous sacrifice may be required of her before she can get home again.