Bruce Wayne, the millionaire playboy, lost his parents at a young age and now secretly operates as Batman, the well established and loved superhero Batman and legally deputized member of local law enforcement. Aided by his teenage ward, Dick Grayson, Batman and Robin make for an unstoppable force for justice and all that is good. Wayne suspected Grayson was too focused on upper body strength and had him study ballet. Grayson admitted he felt ridiculous in the tights. Wayne informed him ballet would help him with his balance, flexibility, and strength as well as aid him in their never-ending fight against crime. Wayne called it a night and put on the television to Gotham Palace, everyone's favorite variety show. They watched in horror as the Joker, Penguin, Catwoman, and Riddler appeared instead of the episode's scheduled musical guests, Hector and the Ho Daddies. Alfred Pennyworth informed them of the Bat-Signal. Wayne suspected Commissioner Gordon was already calling.
On the way to Wayne's study, they bumped into Dick's Aunt Harriet. To cover their tracks, they told her they were in a rush to go on a relaxing night fishing outing. Wayne answered the Bat-Phone as Batman then the duo went down the Bat-poles to the Batcave. Batman and Robin met with Commissioner Gordon and Chief O'Hara at Gotham City Police Headquarters to go over a riddle left behind by the Riddler. Robin read it aloud, "Poor people have it, rich people need it, if you eat it, you die." Batman immediately guessed the answer was "nothing." Robin started brainstorming synonyms like zero, zilch, and goose egg. He recalled Farmer Jones delivered a shipment of his prize-winning goose eggs to the local market just last week and last Tuesday was the night of the total lunar eclipse. Batman believed the Acme Atomic Energy Laboratory was the villains' target since it just opened a new wing dedicated to the science of total lunar eclipses.
After they parked across the street, Batman stopped Robin from jaywalking and reminded him it was imperative they follow the rules since they were duly deputized officers of the law. Catwoman tried to seduce Batman into giving up being a do-gooder, but he in turn asked her to renounce her ways. Penguin tired of their flirting and bashed Batman in the head with his umbrella. Batman was dazed and saw three Catwomen. The villains managed to get away to the Jokermobile but Batman and Robin followed in the Batmobile. Batman swerved around the Jokermobile's explosives, turned right, and triggered the parachute release. The Riddler tried to deter them by duplicating potholes with the stolen Replica Ray. Batman advised Robin to use the Batzooka but Riddler secured his allies' escape with an improvised trench in the road. Batman and Robin returned to the Batcave with a piece of tin foil that floated down to them.
Batman suspected the tin foil was a lead and submitted it to Bat-Analyzer. It determined there were traces of amorphous semi-crystalline layers. Robin realized that was a starch. Batman noted it was gravy, to be precise, and deduced the villains were hiding out at the abandoned Fitzsimmons Frozen Food Factory. Rather than use the front door and be ambushed, Batman and Robin used the Bat-climb method to scale the side of the factory to an open window. Catwoman agreed to give up but it was a ruse to get them with knockout gas. Batman and Robin awoke tied up and lying in a giant TV dinner resting on a conveyor belt that led to a giant oven. Catwoman attempted to sway Batman to her side with a new mind control serum she called Batnip. Batman's strong moral fiber appeared to prevent him from succombing to its power. The Joker was undaunted and quickly threw the lever for the conveyor belt and left them to fry. Luckily, Batman noticed the lemon tart dessert and used its acidic content to weaken his bonds. Batman freed himself just in time and swung off with Robin in tow.
They returned to police headquarters. Batman sternly admonished Gordon and O'Hara for wasting valuable taxpayer's money by watching the Belgravian space launch on TV while they were on the job. Gordon and O'Hara were stunned. Batman cut off their sniveling and they also reported the villains had gone quiet. Back at Wayne Manor, Wayne stopped Aunt Harriet from touching the Shakespeare bust in his study and cited the oils from her fingers would ruin the finish. To Grayson's dismay, he watched as Wayne fired Pennyworth for failing to keep Aunt Harriet away from his study and thus, his secret. Wayne insisted it was because the city depended on them. They searched all of Gotham for the villains and even took to air and sea but found no trace of them. Robin mused they either gave up or weren't on the planet. Batman cited Occam's razor and proposed they stowed away on the recent Belgravian rocket launch. Batman and Robin took to the Batrocket. Batman cautioned Robin that space travel was the most dangerous endeavor man had ever embarked on. Robin stated society wouldn't move forward without brave men taking bold risks.
The Batrocket launched and made its way to an abandoned space station. He explained to Robin it was a failed joint venture between the American and Belgravian governments. He was visibly angered myopic pride got in the way of diplomacy. They donned their space suits, activated the Bat-gravity boots, and walked to Airlock 1. They arrived just in time and saved Catwoman from certain death. Robin didn't have much sympathy for her. Batman advised him he would come to appreciate the pungent allure of the feminine mystique when he got older. The villains revealed their plan was to use the Replica Ray to create two more Earths so each one would have a Gotham to rule. Batman was upset by their arrogance and suggested the idea of throwing the remaining villains out of the airlock. Penguin cited by the Marquess of Queensberry, they had to follow a set of rules. Robin reminded him they had to follow the law but Batman recalled their were out of Gotham's jurisdiction. After a jaunt in zero g, Batman restored gravity with a well thrown Batarang.
Surprisingly, he donned a brass knuckle and went nuts on the villains. Robin was a little concerned if they would be okay but Batman insisted they'd live. They realized Catwoman sneaked off into an escape pod to Earth. Batman and Robin returned to Earth with the villains and Replica Ray in their custody. Batman decided to store the ray in the Batcave for safekeeping. To everone's surprise, Batman disappeared out of Gordon's window while he was in mid-speech thanking them. Robin asked them to forgive Batman because he was a little out of sorts from the ordeal. To Robin's shock, Batman took off in the Batmobile without him. He was left to hitchhike back home. Wayne settled in for Gotham Palace but Aunt Harriet teased them about getting home early from "night fishing." Wayne had enough and reduced Aunt Harriet to tears. Grayson declared he had completely changed. Wayne led him outside and implored him to join Pennyworth on skid row if he was so concerned. Catwoman's Batnip, secretly spiked with Joker's Laughing Gas, worked slowly.
Wayne took a sudden unannounced break from crime fighting. Swamped with active cases, the police was overwhelmed. Gordon tried calling the Bat-Phone every 20 minutes but got no answer. Wayne had enough and ripped the Bat-Phone out of the wall. He suited up and decided to take over Gotham City. He started by replacing important positions with clones of himself made with the Replica Ray, including Commissioner Gordon, Chief O'Hara, and Mayor Linseed. The city was soon overrun with Batmen. Batman even started to set his sights on taking over the world. He traded the Batmobile in at the Custom Meisters for a souped up Bat-Hot Rod. Robin realized what happened and went to the Kit Kat Kave in search of Catwoman for an antidote. Anticipating Batman would be waiting for them and try to kill them in the atomic pile, Robin sprayed himself and Catwoman with Bat-Anti-Isotope Spray. Batman was waiting as predicted. He offered Catwoman the chance to join him and they'd kill Robin first. Against her better judgment, Catwoman blew the antidote into Batman's face.
The cure was ineffectual as he coated himself with Bat-Anti-Antidote. Batman and Robin engaged in a utility belt showdown but it was draw. Catwoman had enough and attacked with her whip. Batman caught it and threw Catwoman into Robin then sprayed them with Bat-Knockout Gas. They awoke tied to a special Bat-cable and dangling over the atomic pile. Batman excused himself to go continue ruling Gotham City. Catwoman was unable to cut through the cable and the railing was raised three inches to prevent a clean swing. They Anti-Isotope Spray prevented their assured deaths. In need of an army crazy enough to fight Batman and his duplicates, Robin and Catwoman disguised themselves as prison inspectors and entered the Gotham State Penitentiary, where they springed 14 inmates. Batman still craved attention to feed his insatiable egomania. He and his clones took over Gotham Palace. Batman took over as the host and had his clones outfit Bat-VHF Detonators to every TV aerial in Gotham City. He warned viewers if they changed to channel or turned their TV off, they would explode. Robin and Catwoman, backed by their new allies, entered the palace and confronted Batman. Not entirely surprised of their survival, Batman declared the show must go on. While he danced to his theme song, Robin and Catwoman forces took on the clones but were defeated. Batman decided to kill the two with his bare hands but he was interrupted by a delivery from an admirer congratulating him on being Gotham's new pop star. Without thinking twice, Batman took a drink from the champagne bottle and was cured of the Batnip and Bat-Anti-Antidote. The duplicates turned on Batman but soon combusted into harmless piles of yellow muck due to the instability of the ray's abilities to replicate living beings. Gordon and O'Hara commended Batman for saving the day but he credited Robin and Catwoman. He pointed out this proved even the most vile, depraved, and amoral villain was capable of redemption. Catwoman was "thrilled" with his kind words. Batman understood Catwoman still had to serve her time and promised to act as a character witness on her behalf.
Catwoman had a better idea for him to show his gratitude and kissed him passionately. After she left in Gordon and O'Hara's custody, the deliveryman revealed himself to be Pennyworth. They explained they had a long standing plan in case he was brainwashed. If he were ever fired, Pennyworth was instructed to prepare an antidote from a precise set of instructions and list of ingredients. Robin was impressed Batman was one step ahead as always. Batman realized he was used by Joker, Penguin, and Riddler as a distraction all along. They speculated the villains were conducting an art heist and ran to the Batmobile to find Catwoman waiting. Batman decided to grant her request to join them to stop the villains. The villains retreated to their getaway vehicle, the Pengyblimp, but the trio caught up in the Whirly-Bats. Batman and Robin took out the blimp's booster jets with well timed and thrown exploding Batarangs. They boarded the blimp and made it to the top for the final battle.
The three henchmen, Stanley Laurel, G.O.O.N., and Down, were tied up by Batman and Robin then left hanging off a flagpole. Riddler, Penguin, and Joker tried to bail on the blimp but were each hoisted on their own petard. Catwoman attempted to flee with the stolen art and treasures. Batman begged her to reconsider. She offered to give up if he ran off with her to Europe to sip tea in cafes and live happily ever after. He declined. Turbulence knocked the goods into Robin's hands. Batman held out his hand to her but watched as Catwoman drop down through a factory smoke stack rather than go to prison again. Batman mourned her and declared loving her was wrong but he had to do right. Wayne and Grayson threw Aunt Harriet a surprise birthday party at Wayne Manor. She apologized for being so insecure and declared she knew she was a valued member of the family. Pennyworth informed Wayne on the sly about the Bat-Signal in the sky. Wayne and Grayson excused themselves to go skeet shooting just as the party started, leaving Harriet confused as always.