Two Jesuit priests travel to seventeenth century Japan which has, under the Tokugawa shogunate, banned Catholicism and almost all foreign contact.

Takeshi Hongo is a promising young man with a passion for motorcycle racing. However, his dreams are suddenly ruined when he gets kidnapped by Shocker, the evil secret organization planning to dominate the world. After being remodeled into a cyborg, Takeshi escapes and swears to protect the world from the inhuman monsters.