The natives of the island of Hikueru in the South Pacific ocean tell the legend of a boy named Mafatu and his dog, Tambu. Mafatu's father was lost at sea, causing him to fear the ocean and suffer from nightmares. Realizing that he will someday be chief of their tribe, he must conquer his fear. He and Tambu set sail in a small canoe. His fears prove to be real when a storm forces him ashore on an island claimed by a savage tribe.