After Kengo reaches a dead end in finding out the identity of the mysterious new Rider, Sonoda-sensei introduces new transfer student, Ryuusei Sakuta.

Ryuusei tries to gain membership to the Kamen Rider Club to further his own agenda but whilst most of the Club is fine with a new member, Gentaro is against Ryuusei joining...

Gentaro and Kengo must find a way to overcome their rift before a powerful Zodiarts defeats both Fourze and Meteor.

The Cancer Zodiarts threatens the members of the Kamen Rider Club now that he has attained the Supernova ability. While he still cannot transform, Ryusei discovers that Jiro's condition has taken a turn for the worse.

Gentaro and his friends enter the third-year class headed by Mr. Ohsugi, and Gentaro tries to befriend new first-year students Haru and Ran. However, Haru is given a Zodiarts Switch by the Libra Zodiarts.

After Gentaro's death at Ryusei's hands, Kengo does not know how to resurrect him as the Aries Zodiarts takes the other Kamen Rider Club members captive. Elsewhere, having betrayed Tachibana, Ryusei is able to talk to the revived Jiro.