Following their failed escape attempt, Gear, White Bear, and Qu-0213 are imprisoned on a secluded island surrounded only by the sea. As they adapt to life behind bars, they unexpectedly cross paths with the assassin Cook siblings.

After a fierce struggle, Gear, White Bear, and Qu-0213 finally reach the deepest part of the capital's underground. To destroy the core of the system, they head through a door, eventually arriving in a pitch-black space. A spotlight flickers on, revealing a mysterious figure.