Leaving his home in the hidden valley, young Toca must journey for a sun season to and from the endless water in order to prove his manhood. He must accomplish the tribe’s Katata Ado if he is ever to become chief. Before leaving, old Chief Acuta secretly gives Toca – whose spirit image and talisman is the Black Ghost – instructions for him to bring back three vital things. If he fails, the old chief has foreseen, over the past generations, that their people, the Nashua, will cease to exist.

Early in Toca’s journey through the dense rain forest of the Amazon, he encounters a young girl his age, named Shana, and her father who are not from the Amazon and are lost. They desperately need help to survive in this deadly environment.