Green Lantern seeks Batman’s help in locating renegade Green Lantern Sinestro, but when the villain comes to Earth, Penguin ends up with the hero’s power ring.

With the help of a hacker, Joker’s mind is downloaded into a computer, enabling him to control the new WayneTech Nanobots. This creates a new and improved body who attempts to destroy Batman, Robin, and the original Joker.

A trio of college misfits use stolen mutagens from Doctor Kirk Langstrom to mutate themselves into human-animal forms and get revenge on those who have scorned them.

Gotham citizens are bursting into hysterical laughter and dumping their stolen goods into the river, putting Batman, Robin and Batgirl onto the trail of The Joker, who is using a steam train to commit his new crime wave.