The 2001–2008 storyline arc of Bionicle was set in a science fantasy world inhabited predominantly by part-organic, part-machine beings in a subterranean world, which exists in massive domes underground. This world (dubbed "The Matoran Universe") and its races were once protected by a Great Spirit named Mata Nui, until he was cast into an eternal slumber by the evil Makuta Teridax and the Brotherhood of Makuta. The world of the Matoran began to fall apart. But mask of life that was stored inside Mata Nui was sent out to space to find a new planet. The mask landed on the planet of Bara Magna and the mask created a small body.