This is Kamen Rider W stripped down to pure noir detective work, where the mystery matters more than the suit. The animation is so sharp it makes you forget you're watching an adaptation of a 2008 tokusatsu series, and the saxophone doesn't just score scenes, it IS the show's backbone, bleeding into every frame. You need to have seen the original series first, which means this isn't gateway content, but what you get is a 12-episode noir film masquerading as a Kamen Rider story, where the detective work between transformations hits as hard as the fights themselves.

Fuuto's streets hide a dangerous secret: Gaia Memories, small devices that transform ordinary people into powerful monsters called Dopants. The police are helpless against them. After the death of his boss, hard-boiled detective Shoutaro Hidari teams up with the mysterious Philip to investigate crimes involving Dopants. Using Gaia Memories of their own, the pair combine into Kamen Rider Double to protect the city. But these devices come with a price, carrying a toxin that can drive users to madness and death. Although most Dopants have already been stopped, some remain at large. When a mysterious woman named Tokime appears and becomes linked to a string of murders and thefts, Shoutaro and Philip must fight again while working to learn who she really is.