Batman is the main hero of Gotham City and teams up with Superman the rest of the Justice League to stop the Joker and Lex Luthor.
In LEGO Batman 2: DC Superheroes, Batman is a main character.
Bruce Wayne and Lex Luthor were the nominees for The-Man-of-the-Year award, and at the ceremony, Bruce wins. However, the theatre was raided by The Joker, Harley Quinn, The Penguin, The Riddler, and Two-Face. Bruce exits to change into Batman while the villains rampage and Joker steals the award. Just as he is giving his "acceptance speech" Batman and Robin burst through the stage on the Bat-boat. Joker, Penguin, Riddler, and Two-Face escaped through the stage's trapdoor, while Harley fought the Dynamic Duo. She was defeated, and Batman and Robin began to search for and defeat the other villains.
Joker was able to escape the theatre, however, and made it to his boat. He was chased by Batman and Robin in the latter's helicopter with Batman hanging from a rope ladder. Joker threw chattering teeth to cut the ropes, but Batman summoned and landed in the Batwing. Batman and Robin chased him through to the Amusement Mile, where Batman disrupted the water with the Batwing's wing and caused Joker's boat to go ashore. After several failed attempts to destroy the Batwing, Joker was caught in a bat shaped net and sent to Arkham Asylum.
In the Batcave, Bruce Wayne is contacted by Martian Manhunter from the Justice League Watchtower and informs him of an emergency. Alfred shows Bruce and Tim Drake where it is on a map, and they change into Batman and Robin and leave for Arkham Asylum where they find the villains Joker freed attempting a prison break. They then attempt to stop them, starting with Catwoman. The villains are stopped, and the Police arrive. Commissioner Gordon informs the Dynamic Duo that all of the villains have been accounted for, except Joker. Batman notices an electrified brick outside of Joker's cell. He and Robin go to investigate. They run-in to Killer Croc and Mr. Freeze who create obstacles, and stop The Scarecrow from escaping. They bring a black piece back to the Batmobile and discover it was destroyed with LexCorp technology and conclude that Luthor broke Joker out. Batman, Robin, and Gordon are alerted by a Police Officer that there has been a break-in at Ace Chemicals, and they leave. When Gordon and the Officer look back, they realize that the villains have escaped.
At Ace Chemicals, Batman and Robin find that The Joker had already been there and stolen chemicals. They try to escape when a fire begins and just before they fall into the inferno, they are rescued by Superman. With help from Superman, they are able to escape. Batman tries to find out what Joker is making, and realizes it is Kryptonite. He uses the Batcomputer to find nearby locations of Kryptonite, and heads downtown. They follow a large vehicle, the Juggernaut. On the inside, Lex and Joker are creating Kryptonite. Batman and Robin begin firing at it. When the defenses are weakened enough, the Dynamic Duo infiltrate it. Batman takes the Kryptonite, and Lex is subdued. Joker however uses his joybuzzer on Batman and Robin to the point where they fall out of the Juggernaut, into their vehicles. Joker aims the Deconstructor at the Batmobile, which falls apart, and the Juggernaut gets away.
Back in the Batcave, Batman analyzes the Kryptonite and finds that it is only similar to true Kryptonite and that is harmless to Kryptonians. However, if there wasn't actual Kryptonite in the Juggernaut, the Batmobile's computer shouldn't have shown it. He and Robin decide that it was just a trick of Joker's, and put it away with the other Kryptonite they store in-case Superman goes bad.
Lex and Joker enter the Batcave, since the "Kryptonite" had a homing signal. A fight ensues, and the Bat-bike, Batwing, and Batboat are destroyed. Batman and Robin flee through the elevator, and hang on to the shaft to escape when it falls. Joker and Lex find the Kryptonite vault and leave with it after Joker's pies explode and a fire begins. At the top of the elevator shaft, Superman arrives to rescue Batman and Robin. Together they escape the Batcave. Batman and Superman head after a LexCorp aircraft while Robin stays and tries to fix the vehicles.
Batman and Superman infiltrate the LexCorp aircraft, but when the reach the control section, Batman is dropped through a trapdoor. Superman rescues him and carries him to LexCorp in Metropolis.
From LexCorp, a large Joker-esque robot emerges and heads back to Gotham. Batman in a LexCorp aircraft and Superman fire at it, and then land on it. Lex emerges with Kryptonite and weakens Superman who falls. Batman saves him by gliding back to Gotham. Though most of his powers return, he is unable to fly and hunches over.
The robot hits at them, and they fall through the ground. It continues to make holes in the ground above the metro, but Superman uses his heat vision to destroy the left hand completely.
At the City Hall, Lex begins to give a speech and infects the crowd with a mind-altering gas so that they will vote for him. Superman destroys the gas emitting flower from the robot.
Robin arrives in a multi-coloured Batmobile. The robot chases Batman and Robin through Gotham City, but they drive in such a way that the Kryptonite it leaves looks similar to Joker's face.
Martian Manhunter sees it from space, and calls the Justice League to Gotham. Wonder Woman, Green Lantern, Cyborg, and The Flash respond.
The robot attacks Wayne Tower, since Lex despises Bruce, and destroys the foundation. Superman and Wonder Woman keep it in place while Batman, Robin, Green Lantern, and Cyborg enter through the bottom of the building together. They knock the Robot off of the top and Green Lantern creates constructs to keep the tower from falling.
Superman is too weak to continue, but Batman, Robin, Wonder Woman, Green Lantern, Cyborg, and The Flash finish it off. Joker is defeated, and Lex emerges in power armour. Batman contacts Martian Manhunter who readies the Watchtower laser. Robin helps aim it, and Lex is defeated.
His dog, Ace the Bathound is mentioned during Vicki Vale's news reports. He, Krypto the Superdog, and Stretch-O-Mutt are nominees for the "Dog of the Year" award.