— 東映特撮ファンクラブ（TTFC） (@tokusatsu_fc) May 7, 2022
The story revealed so far states that the Kougami Foundation has developed a new Birth System called the Birth X Driver to fight the resurrected Greeeds, but while they performing experiments for it, the user, Shintaro Gotou disappeared.
The energy supplied to the Driver went out of control, and Gotou is sent to a parallel world. In this world, Hina Izumi is Kamen Rider OOO, and everyone we know are significantly different from the world Gotou was originally! Things get more confusing as more confusing things started to happen one after the another! Who will help Gotou find his way back to his original world?! With it be Eiji, the Greeed, or the mysterious “doctor”?