Story takes place after the events of Kamen Rider Zero-One the Movie: REAL×TIME.
ZAIA Enterprise CEO Rion Arkland had taken away MetsubouJinrai.net's Jin (Kamen Rider Jin). Horobi (Kamen Rider Horobi), Ikazuchi (Kamen Rider Ikazuchi) & Naki (Kamen Rider Naki) goes to rescue Jin. But over there they witness the Mass Produced Soldier type Humagear called "Sold".
Rion's motive is to produce the Solds in large quantity and sell them all over the world. The Solds are said that they can't attain singularity. But Jin feels that it is wrong to be use Humagears as Weapon. He tells Horobi and others, "I want to free Solds".
The four transform into Kamen Rider in order to free the Solds. But at that moment, something happens to Jin. Just what had happened to him? Rion did something to him after he was captured?
Just like Rion's plan, Humanity's Ultimate Threat was about to be born in an unexpected away.
By Ultimate Threat, are they talking about Ark? Are they going to turn Jin into Ark once again?