Lex Luthor is running for president, but his poll figures are terrible. He learns that the Joker knows how to produce more Kryptonite, and can make a gas that makes people love him, which will help Luthor win the election and defeat Superman. He breaks the Joker out of Arkham Asylum and promises him the use of Luthor's De-Constructor weapon to defeat Batman by dismantling all his shiny black toys. Batman and Robin investigate the breakout, which leads them to Ace Chemical, booby-trapped by The Joker after a visit to gather materials for the gas and Kryptonite. Superman rescues the Dynamic Duo, but Batman is rude to him (concerned he might go rogue some day) and he leaves. Batman traces Luthor's mobile lab and snatches the manufactured Kryptonite, but the Batmobile is deconstructed. At the Batcave, he determines the new Kryptonite is harmless, but it proves to be a tracking device which leads Luthor and Joker to the cave—Batman has a Kryptonite Vault, which The Joker knew about. Using explosive pies, the villains destroy the cave, escaping with a load of Kryptonite, while the heroes are saved by Superman.