When a breakout succeeds in Arkham Asylum, Jason Todd (Robin), ignoring Batman's warnings, gets there. When he arrives, he realizes that it is a trap and the Joker kidnaps him. Batman goes immediately to the Asylum, leaving Nightwing and Batwoman to patrol Gotham, and there, he has to fight his way among his enemies to save young Robin. Meanwhile Joker, to keep the police away from Arkham, threatens to set off bombs across Gotham if any law enforcement is seen approaching Arkham Asylum and sends his henchmen to cripple Barbara Gordon (Batgirl), the commissioner's daughter, as a warning