This is the tale of a man who has yet to realize what his destiny is. Simon and Kamina live in an underground village. But with the sudden appearance of a Gunmen, a gigantic mecha, and Yoko, a beautiful woman who fires wildly with a superconducting rifle, their daily routine is shattered. All together they attack and destroy the enemy robot. Their momentum will carry the trio up to to the surface… into a world of danger and adventures.