Nagi is a diver from a quiet fishing village where a series of strange incidents have been occurring recently, including residents that have gone missing. One day, a stranger takes her to an office where she is asked to recover sunken treasure at Kaijin Reef. Nagi agrees to do so, but during her dive, she gets exposed to strange radiation. Afterwards, she starts to experience moments where she exponentially grows in size. This causes a lot of problems for her and the people surrounding her.

Intercepting the transport carrying Foundation X’s new 2nd generation Gaia Memories, the special-ops unit NEVER, led by Daido Katsumi, intend to turn Fuuto into Hell on Earth. With Daido wielding the T2 Eternal Memory and a Lost Driver, granting him power in the form of Kamen Rider Eternal, Fuuto’s Kamen Riders are left powerless as Daido and his allies take control of Fuuto Tower, converting it into a massive laser weapon…