Set in 2008, Kurenai Wataru is a young man who is destined from birth to become Kamen Rider Kiva, and to fight rampant race of monsters known as Fangires, which sustain themselves by draining human life. Though fighting on the side of humanity, Kiva is targeted by an organization which seeks to protect the human race from other races, thus seeing Kiva as a threat. They have a soldier on their side, Kamen Rider IXA, who possesses abilities matching those of Kiva's. As the story progresses, he will come across another Rider, Kamen Rider Saga, who is connected to him in ways he had never imagined.
Simultaneously, the story of Wataru's father, Kurenai Otoya, is told. With the time set in 1986, 22 years ago, Otoya's story will reveal the origin of Kiva, and how Wataru's destiny came to be.