Set in Nijigao City, where nature and civilization are in complete harmony. However in this city lies a secret and evil society known as the Chaosism, where they operate behind-the-scenes. One day, the protagonist learns of the existence of a certain Kamen Rider who lost his true memories due to his human body modifications from Chaosism.The main character (you), who has inherited the role of agent from your late father by supporting the Kamen Riders, must change the predetermined destinies of 16 Kamen Riders, all of different ages, occupations, beliefs, and self-individuality, and fight to restore their memories.