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.

A horde of assorted Mirror Monsters roam a warehouse, a mysterious figure resembling Agito Burning Form calling for the Kamen Riders to come fight them and die.

Shouichi encounters a teenage girl called Sayaka, who ran away from a military facility because of an attack by the Ant Lords. Sayaka has a supernatural ability to foresee the future. Risa Fukami, of the military group GA, wants to use that power to enhance the newly-made G4 System, which was based upon designs stolen from Ozawa. Now, Agito and Gills must fight to stop the Ant Lords' attack, as G3 and G4 settle their score.

Kamen Riders Agito, G3 and Gills help Televi-Kun against Lords.

Shouichi encounters his old friend and caretaker Dr. Higashi Kunieda. Dr. Kunieda, a friend of Yoshihiko Misugi, took care of him while he was hospitalized with amnesia. After catching up on a year of separation Shouichi abruptly leaves to house to fight an Unknown as Agito Burning Form. Unfortunately, after the Unknown flees Shouichi loses control of himself and attacks Dr. Kunieda, who followed Shoucihi and watched him transform. Dr. Kunieda managed to calm him down but Shouichi becomes to afraid of himself and runs away.