In a world where giant monsters have been in conflict with humanity since 1958, Ray, a young boy seeking to avenge his father, seeks to become part of the giant robot program that defend humanity, even though his paternal grandfather warns him not to become bloodthirsty against the beasts.
Eventually, Ray and his new friend Yuriko discover that the rise in monster attacks was manipulated by General Parker, the narcissistic General in charge of the robot program, as a means of becoming a war hero and the monsters' aggression was manipulated by tracker tags invented by Parker.
Soon, Ray and Yuriko seek out to expose Parker and allow humans and monsters to peacefully co-exist.
