A novelist receives a letter from a female university student named Kubo about strange sounds that emanate from a room in her apartment. They begin to investigate incidents involving former residents, and eventually discover the shocking truths lurking inside the building.

This movie is an alternate ending to the series, taking place after the events of episode 46. With only six Riders remaining in the Rider War, Shirō Kanzaki feels that time is running short.

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.

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.

In the near future Japan's economy is in shambles and bet bowling is huge. Team Kingpin hopes the government will ban bet bowling so they can open a casino. The team full of beautiful girls, team allways, engages in a fierce battle to stop them.

All the incidents occuring around the Girls Remix up to this point were part of Sumire Kurono's plan to create the ultimate Kamen Rider. Now that plan is moving into its final phase. Sumire kidnapes Nayuta Mikazuki again. After performing her final surgery, "Kamen Rider Eins" is finally born. Will the Girls Remix be able to get Nayuta back? And what will become of Nayuta, who has become Kamen Rider Eins?

In a world where people awaken to supernatural powers, one ordinary police officer Makoto Hikawa stands against this chaos.