The Blue World, a world symbolizing reason, is under attack by fierce creatures known as the Nightfly O'Note sent from the Red World, a world symbolizing instinct. Elected to lead the Blue World, 17-year-old researcher Akira Asagi will take charge of the combat unit “IS”. These six riders, also called the Scared Rider Xechs, will fight at the Ryuukyuu LAG to protect their world and each other.