Yuta's teacher gives him a photo of the desert near the Dunhuang Caves in China. As Yuta daydreams about finding the treasures of the caves, he is miraculously transported there. However, the treasures he discovers are way beyond what he had imagined.

Joe Yuki, one of the coolest DJs in Shibuya, has a secret identity as the leader of gangs. Because of his traumatic childhood, he fiercely hates "weaklings" and sees winning as his only option in life. One night, an old man is being taunted by the kid known as "the human punching bag." The old man reminds Joe of his parents and childhood, and he uncontrollably challenges the kid to a fight. A fight in which he's defeated, and his pride is utterly shattered into pieces.

As a baby Jiro was delivered to his foster parents by a massive oni, who said he would return for Jiro in 15 years. When the time comes Jiro must contend with enemy oni, dark cultists, and their minions while attempting to protect both his parents and girlfriend from their depredations. Ultimately he must embark on a journey through the past, future, and other dimensions to embrace his destiny as Shuten Doji reborn.

"How were Gaia Memories created?" "Why did W begin to fight?" To answer Tokime's questions, Shoutarou quietly begins to tell a story. He speaks of his meeting and parting with a man he admired and called his old man—his mentor, Soukichi Narumi. Mysterious people called Dopants, who utilized the powers of Gaia Memories, had begun appearing in the shadows of Fuuto, the windy city. A young Shoutarou had become an assistant of the detective Soukichi and, though called half-baked, began to follow in his footsteps. Unaware that, in addition to his detective work, Soukichi was secretly acting as Skull, Shoutarou began to grow frustrated with his mentor. That was when the Narumi Detective Agency received a phone call—a request from Hell inviting Shoutarou and company to a fateful night! When Shoutarou tracked down Soukichi to deliver the "trump card" bestowed by the mysterious caller, what did he see? Shoutarou and Philip. The one detective made of two and the night when Kamen Rider W began. That whole story will finally be revealed. (Source: Official site, translated)