The Rider War has re-erupted as Tsukasa now embraces his title as the "Destroyer of Worlds". He goes on a rampage as Decade and defeats Rider after Rider. However, the one to stand against him was Natsumi, who decided to gain the power of Kamen Rider Kiva-la to stop him. In the midst of their battle, Narutaki has formed a new organization, Super Shocker and plans to give birth to the ultimate life-form with the "power to surpass God", which could be his trump card for finally achieving world domination. On the night of Christmas Eve, the Narumi Detective Office receive a strange request relating to Shotaro's former mentor, Sokichi Narumi. On the case, Shotaro's confidence is shattered following a shocking revelation regarding Sokichi. To help him regain it, Philip takes Shotaro to a certain location... the place where everything began.
