Yasuharu Miura

Professor Daidōji has developed a gravity machine called the GX Device. Unfortunately, Shocker wants it; so they attack the professor and destroy his laboratory, but come home empty-handed. Shocker's agents find out that the plans for the GX Device are with Daidōji's daughter, who is celebrating her birthday. Now the Kamen Riders, along with FBI agent Kazuya Taki, must protect Daidōji's daughter and prevent Shocker from obtaining the plans.

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.