Amid the protests of both human rights groups and Bruce Wayne, a new Arkham rises. The Joker is scheduled to be its first inmate, but not if Harley Quinn has anything to say about it. Meanwhile, Batman's suspicions lead him to investigate just who is really behind this new, more sprawling asylum and what their motivations might be.
Batman investigates the new Mayor of Gotham only to encounter the real power behind Arkham City, Hugo Strange. Meanwhile, Harley Quinn rescues the Joker from his murderous jailers.
