A great comet hurls from space and collides with Earth, causing a cataclysmic earthquake that rocks the Kanto Plain of Japan, killing several and reducing the cites to rubble. In this time of weakness, a ruthless man known as the Slum King took control of the Kanto Plain with his brute force and rules it with an iron fist. However, in the middle of a trek across the land with his great forces at his side, he encounters a mighty beast-like man wearing a battered green jacket and a yellow ascot who slaughters his men and then targets the Slum King himself. They clash, but their fight is interrupted by a sudden massive tsunami that separates the two.