When the Key steals a priceless piece of encryption software only to get arrested, Batman must turn himself over to Harvey Dent so that he'll be locked up and can get the Key out and into Federal custody. However, the head prisoner,huger Croc, plans to make sure that Batman doesn't leave Blackgate alive.
Batman once more patrols the streets of Gotham City. Batman brings justice to the likes of The Joker, The Penguin, Professor Pygg, and more treacherous forces seeking to blanket the city in their arcane menace.
Along with backup from ex-secret agent Alfred and lethal swordstress Katana, the Dark Knight faces the twisted machinations of Gotham City's criminal underworld led by the likes of Anarky, Mister Toad and Magpie.