Depicting the aftermath of " Kamen Rider Zero One REAL x TIME the Movie ", the four members of Mestuboujinrai; Horibi, Jin, Raiden and Naki, are on the path of coexisting with humankind. Together, Jin and Horobi continue to work so that malice cannot occur in the world, whilst Raiden works as an astronaut at the Space Business Center of Hiden Intelligence and Naki works as a technical advisor to the artificial intelligence special agency "AIMS" to crack down on AI crimes.
However, a man appears before Jin, announcing, "I have come to collect you" which causes Jin to become uneasy. Whilst the four are all together, Horobi states "This is a holy war", whilst raising his sword. Is Horobi turning his back on humankind after all? And who is the mysterious man with an interest in Jin?