One day, a mysterious letter 'F' starts to be written on doorplates in a condominium building. Since then, mysterious incidents consistently occur around Yukari Yamamoto, who is an ordinary female high school student living in the building.

After witnessing a strange explosion, Shinnosuke Tomari is later visited by a young man claiming to be his son Eiji Tomari from the year 2035. Eiji warns Shinnosuke that a year from now, Mr. Belt's AI will go berserk and lead to the Roidmudes overtaking humanity. However, Shinnosuke cannot immediately deal with this new information when the evil Kamen Rider Dark Drive also comes from the future, causing enough mayhem that leads to Shinnosuke being framed for it and becoming the public's most wanted.