After the Joker fails to defeat Superman and Batman, Lex Luthor tries to withdraw from the deal by killing the clown. This fails and leads instead to the Joker and Harley Quinn trying to take revenge on him by destroying Metropolis in a giant wing, while he uses the other half of the Kryptonite to try to stop Superman. It is ultimately up to the Man of Steel and the Dark Knight to stop this madness.

When an evil demon named Lord Karkull is unleashed, Superman attempts to enlist the aid of the now uninterested wizard superhero, Doctor Fate.