The tale follows a man who has yet to comprehend his fate. In a far-off future, humanity dwells deep underground, prone to the dangers of earthquakes and landslides. Among the dwellers are two young men: Simon, shy and inexperienced, and Kamina, who steadfastly believes in an uncharted world above the earth. Their destinies intersect when their village is destroyed, courtesy of a colossal Gunmen and Yoko, a striking woman with a superconductive rifle, both from the surface. The trio team up, piloting the newly unearthed mecha Lagann to scale the surface, only to discover that Kamina's idealized world is ruled by the Spiral King and his pack of beastmen. Despite the bleakness of their environment, Kamina, Simon, and their accomplices strive to defeat the Spiral King and forge a brighter tomorrow using Gurren Lagann.