A powerful Time Jacker named Tid appears and creates two powerful warriors, Another Double and Another Den-O and orders them to pursue a young boy named Shingo. While Sougo Tokiwa attempts to protect him, he meets a young Kamen Rider fan named Ataru, who demoralizes the existence of the Kamen Riders. What does he mean? Meanwhile, Sento Kiryu attempts to take on Tid alone, but is brainwashed and manipulated by the Time Jacker as a result. With the mystery uncovered, Sougo and Sento head to the Kurogatake Mountains where they must face their true enemy.