On a farm in the interior of Mato Grosso, the impetuous hillbilly Juba grows up free and without instruction, in contact with nature. His parents are killed by cattle rustlers, and he takes over the farm. With the help of the Indian and tutor Iru, who teaches him the secrets of the forest, Juba plans to take revenge on the murderers. His life changes when he falls in love with Ruth, a young woman from the big city who introduces him to a world with new possibilities.