Hugo Strange creates a AI database called DAVE (Digitally Advanced Villain Emulator), encoded with the minds of Gotham's greatest criminals, in order to better predict their crimes. However, DAVE breaks free and proclaims himself to be "Gotham's ultimate criminal mastermind".

Hugo Strange infects the population of Gotham City with a virus that transforms them into zombies, and only Batman and Robin are left to find and distribute the antidote. But when Robin falls, only Batman can save the day. But not everything is at it seems ...

The villains of Gotham City are disappearing, each one defeated and captured by an invisible vigilante named Rumor. Batman and Robin must defeat Rumor before he has a chance to execute the villains.

The heroes fight their android counterparts to recover the Justice League's powers, while the Joining prepares for its final assault on Earth.