Terui Ryu is a young police superintendent in charge of investigating paranormal crimes. However, he loathes his host city, and only does his job to find the "Man with the WMemory", who killed his family.
Unlike Double, Ryu only needs himself to turn into Accel, a red Rider with the ability to transform into a motorcycle. He also has the ability to transform into the blue, speed-oriented Trial Form, as well as the all-around Booster Form but only in W Returns.