The Joker here is a bit more of a softie -- still a madman, but one that knows the bond of hatred between himself and the Batman needs to be reciprocal so that he can be the yin to his yang. To cement himself as #1 on Batman's hate list, Joker and a host of other baddies of assorted popularity are out to destroy Gotham City. Batman catches Joker in the act, but still sees him as just another perp to thwart, hatching bigger and bolder ideas to come from the clown madman in trying to assure arch-nemesis status, starting with springing the worst of them from the dreaded Phantom Zone.