Once the ruler of an entire universe, the Great Spirit Mata Nui finds himself cast out of his own body, his spirit trapped inside the fabled Mask of Life, hurtling through space. After landing on the faraway planet of Bara Magna, the mask creates a new body for Mata Nui, who unwillingly gets caught up in the furious battles of the nearly barren and dangerous planet. The locals, called Agori ask for his help against the unrelenting army of the Rock Tribe, called the Skrall and their leader, Tuma.