In the late 1880s off the coast of Africa, a young couple and their infant son escape a burning ship and land on the unexplored rainforests of Africa, where they craft themselves a treehouse in which to live using salvaged ship parts.
Meanwhile, a gorilla couple named Kerchak and Kala are traveling with the rest of their group when their infant son is killed and eaten by a leopard named Sabor. The next day, the still-heartbroken Kala hears a distant child's cry and, following it, stumbles upon the treehouse. She enters the treehouse to find it trashed, and blood covered paw prints on the floor. Although the infant has survived, both his parents are dead. Kala rescues the baby from a still-hungry Sabor and returns with it to the rest of the group, but Kerchak despises the boy for his appearance.
Nevertheless, Kala decides to raise the boy as her own, naming him Tarzan.