As Shinjiro investigates the portal, he meets Ryuki, a Kamen Rider who has been sent to the human world to defeat his enemies. Ryuki is on a quest to find and seal away eleven other Rider Belts, powerful artifacts that grant their wearers immense power. However, Ryuki is not the only Rider in the human world; another Rider, Knight, is also searching for the belts, with more sinister intentions.