The year is 20XX. Mysterious huge robots called "Giant Robo (GR)" started to appear all over the world and destroy cities. The earth was covered with fear. And their next target is Japan! The hero of this animation Daisaku Kusama, who works in a diving shop, encounters a mysterious girl, simply called V who leads him to make a contract with an enormous robot "Giant Robo 1 (GR1)" at the ancient ruins (Minami Yonaguni...