In 2039, Mother Tower, the first experimental robotic factory in the world, was under construction on Island 8JO, which was controlled by the super computer, Kairon 5. At its central base, fourteen years ago, Kairon 5 declared war against the whole world, which led to mankind surrendering unconditionally. A few years later, a Japanese youngster finds a legendary fighting machine called Gunhed Unit 507 and uses it to begin fighting against Kairon 5.