In Gotham City, Batman is fighting Man-Bat at the museum when he is then ambushed by Penguin. Superman arrives in Gotham City where he wants Batman to join his new superhero team called the Justice League, but Batman prides himself on being a self-sufficient loner. To Batman's annoyance, Superman aids him in fighting Man-Bat, Penguin, and Penguin's Robo-Penguins even when Joker joins the fight. After he defeats Penguin, Man-Bat, and Joker, Superman flies out, but he then disappears along with the villains and the gem.
Because of his disappearance which is even reported by Lois Lane, Batman calls in the Flash to help with his search for Superman. The Flash travels around the world with Batman following in the Batwing until they find Captain Cold trying to steal an obelisk in Egypt. Flash and Batman fight him, but Flash disappears mid fight while Batman is frozen solid without his utility belt. Batman thaws and defeats Cold, but he and the obelisk disappear. Upon finding Atlantean symbols on the obelisk before its disappearance, Batman decides to make another call.
Batman then asks Aquaman for help in the Batboat as they search under the ocean. They find Black Manta and his robot sharks trying to steal the Trident of Poseidon. Batman once again wins the fight, but Aquaman, Black Manta, and the trident all disappear.
Batman then goes to Metropolis where Wonder Woman and Cyborg are fighting Lex Luthor who is trying to steal the Daily Planet Globe for an anonymous buyer. Once again, the Justice League members disappear, Batman defeats Lex Luthor, but he and the globe disappear.
Batman deduces who is behind it, and travels to the Justice League headquarters at the Hall of Justice (the last place he wanted to go). Once there, he identifies Bat-Mite as the culprit as Bat-Mite emerges from the shadows. Bat-Mite has prepared a trap for the Justice League including all of the stolen items. Batman does nothing which Bat-Mite did not expect. But he did hint them that since the cage was immune to their powers, they shouldn't use them, and they escaped by opening the door. Batman promptly accepts the invitation to the Justice League. Bat-Mite summons the villains, but they are easily defeated by the combined might of the Justice League, so Bat-Mite decides that instead of cheering on one hero, he should cheer on an entire team. Before disappearing, Bat-Mite makes the villains disappear.
The rest of the Justice League is pleased that Batman is on their team as Batman laughs with them.
