Posing as lovers on vacation, Motoko and Batou work to try to stop a terrorist organization whose symbol is the Scrasath. Meanwhile, Togusa investigates a murder of a man who possessed a prosthetic leg manufactured by the Mermaid's Leg corporation.
Freed of her responsibilities with the 501 Organization, Motoko Kusanagi must now learn how to take orders from Aramaki. Someone hacks the Logicomas, and Batou enlists the help of former army intelligence officer Ishikawa and former air artillery expert Borma. Kusanagi also seeks to enlist ace sniper Saito and undercover cop Paz into the new Public Security Section 9.
The story is set in 2027, one year after the end of the fourth non-nuclear war. New Port City is still reeling from the war's aftermath when it suffers a bombing caused by a self-propelled mine. Then, a military member implicated in arms-dealing bribes is gunned down. During the investigation, Public Security Section's Daisuke Aramaki encounters Motoko Kusanagi, the cyborg, wizard-level hacker assigned to the military's 501st Secret Unit. Batou, a man with the "eye that does not sleep," suspects that Kusanagi is the one behind the bombing. The Niihama Prefectural Police detective Togusa is pursuing his own dual cases of the shooting death and a prostitute's murder. Motoko herself is being watched by the 501st Secret Unit's head Kurutsu and cyborg agents.
The final live stage event for the Kamen Rider W series, it takes place after the main TV series. In this stage event, Akiko accidentally becomes the Fuuto Dopant after meeting a Shinkurou Isaka from an another world.
A series of 26 net movies, comedy-themed shorts (one for every letter of the alphabet) that were released by Toei to promote the Kamen Rider W summer movie, Kamen Rider W Forever: A to Z/The Gaia Memories of Fate.