Rinko Murakumo used to be a detective until she shot a serial martial arts murderer and resigned from the force. Her daughter went missing during the incident and she has spent years looking for her. One day, she stumbles upon a human trafficking case and surveillance footage from the crime scene shows a woman who looks like the one Rinko suspects took her daughter together with someone who might possibly BE her daughter…
Shigeru Daimonji, the Secretary of National Defense, has ordered Yua Yaiba/Kamen Rider Valkyrie to eliminate Kamen Rider MetsubouJinrai. While she hesitates to act on this directive, the Rider itself sets sights on Valkyrie. Meanwhile, the now former Solds attempt to discover freedom for the first time without ZAIA Enterprise, while engaging in an all out war against A.I.M.S. Isamu Fuwa/Kamen Rider Vulcan, who personally witnessed the birth of Kamen Rider MetsubouJinrai, investigates to discover their true goal. What is Yua's fate, who acts on her own justice as she refuses to fight both Kamen Rider MetsubouJinrai, the Solds, & Isamu who is determined to carry out his final mission as Kamen Rider Vulcan?
ZAIA Enterprise CEO Leon Arkland has abducted Jin away from Metsuboujinrai.net. A large number of soldier-model Huma Gears "Sold" were seen by Naki and Ikazuchi while rescuing Jin. The intention of Leon Arkland was to mass-produce "Sold" and sell them as weapons all over the world. Jin is indignant at the fact that Humagears are about to be used as a weapon, and tells the other members of Metsuboujinrai.net that he wants to free the "Solds". Four people who transform into Kamen Riders will fight to release the "Solds". However, something unexpected happened... What happened to Jin, while he was captured by Leon? According to Leon's plan, the being that poses the "greatest threat" to humankind is about to be born in a surprising way...
A mysterious man called Es/Kamen Rider Eden has emerged, committing simultaneous acts of terror across the world, with thousands of believers following his faith. While the people fall one by one and the world delves into chaos, Aruto Hiden stands up to stop him. Isamu Fuwa, Yaiba Yuia, Gai Amatsu, plus Jin and Horobi of MetsubouJinrai.net also transform into Kamen Riders and fight against the enemy while struggling to seek the truth.
Fuwa has been told that his true past, the one that hadn't been falsified, has been "boring and uninteresting", as Yua overhears and notices that Fuwa cannot hide the look of disappointment on his face. "You are Vulcan! Engrave it in your head!" In order to regain his confidence, Isamu Fuwa looks back at his life and battles as a Kamen Rider! However, this plan of his starts to head in an unexpected direction...!