World's Finest

During a stormy night in Gotham City, an antique dealer prepares to close his shop. As he is closing his door, a woman forces her way in. She is Harley Quinn and using a prank music box, she sprays the shop owner with laughing gas. As he laughs uncontrollably, the Joker enters. The Joker looks around and spots a statue of a green dragon. He steals it and heads out.
Later Detective Harvey Bullock looks over the crime scene. He is confused as to why the Joker would steal the statue and ignore the other valuables. Commissioner Gordon is also puzzled because word of the street is that the Joker is looking for cash. Batman arrives and agrees with the two policemen. He examines and later analyzes a bit of green residue that he finds on the statue's base. Batman discovers that the statue is emitting a low level of radiation. He tells Alfred that he is heading to Metropolis.
Sometime later, Lois Lane sits aboard Air Force One. Suddenly, the aircraft that is carrying the president is taken over by hijackers. Soon Superman arrives to save the day. He enters the plane and deals with the hijackers.
On the ground in Metropolis, the president thanks Superman. After the president leaves, Superman apologizes to Lois for shaking the plane up. Lois tells him that she is getting used to it. As Superman is about to leave, Lois tries to ask Superman out. Unfortunately, a bank robbery interrupts her and Superman heads off.
In his Penthouse apartment, Lex Luthor reads the newspaper and grows angry at the press's coverage of Superman. Luthor tells Mercy to prepare his limo. Just after she responds, she is knocked out by Harley Quinn. Luthor heads to the limo and discovers that it is being driven by Harley. She heads into the street and picks up the Joker. The Joker enters the car and tells Lex that he wants to make a deal. The Joker says that he will kill Superman for a billion dollars. Luthor laughs and asks the Joker how he expects to kill Superman when he can't even deal with Batman. The Joker reveals that he has an ace up his sleeve: a green statue made out of Kryptonite. Luthor agrees to the Joker's plan & shake hand. Later Lois and Clark await the arrival of billionaire Bruce Wayne at the Metropolis Airport. Bruce has come to Metropolis to oversee business negotiations with Lexcorp. When he steps out of the plane, Lois is struck by his good looks. Bruce steps up to her and begins a conversation. He offers her dinner and an interview. She accepts and Bruce heads to his limo. Some time later, the Joker confronts a mobster named Ceasar Carlini. The Joker tells Carlini that he needs a place to stay. Carlini orders the Joker killed, but Harley Quinn knocks out his gang. The Joker uses laughing gas on Carlini and throws him out. He tells Carlini's gang that they have a new leader.
In a hospital Superman sees Carlin in a laughing fit. He realizes that the Joker has come to town.
The next day, Bruce Wayne and Lex Luthor oversee a new robot prototype being tested in a canyon. Wayne wants the robots to be used for unmanned space travel. Lex on the other hand believes that the robots have potential military applications. Wayne disagrees and informs Lex that according to their deal, the robots cannot be used for anything without his approval. That evening, Bruce takes Lois out for dinner. They talk about Superman, but Lois tells him that she doesn't want to talk about Superman anymore. He agrees and the two dance. Sometime later, Clark Kent asks his contacts to keep an ear open for word on the Joker. At the same time at a dance club, Batman begins his own investigation. He confronts a former gangster named Binko. He tells Binko that he knows that his former boss Carlini has been replaced. Batman fights off a number of Binko's bodyguards. He grabs Binko and pushes him against the wall. He tells him that he wants to know the whereabouts of the Joker. Batman begins to press Binko, but Superman arrives and tells him to stop. Superman grabs Batman's arm, but using judo, Batman throws Superman across the room. Superman is surprised, but knocks Batman over. Using his X-ray vision, Superman discovers that Batman is Bruce Wayne. He tells Batman that he does not want vigilantes in Metropolis. Batman says that he'll leave after he finds the Joker. He tells Superman that the Joker is out to get him and that he has twenty pounds of Kryptonite. Before Superman can respond, Batman disappears. Superman heads home. He goes to his apartment and changes back into Clark Kent. He gets a phone call from Lois who tells him that she has a date with Bruce Wayne. As he chats, Clark notices a tracking device on his cape. Clark looks out the window and sees Batman watching him with binoculars. Now both of them know each other's secret identities. At the Daily Planet, Lois works on a story and is surprised by Bruce Wayne. When she walks off to talk to Perry, Bruce talks to Clark. He tells him that he has been unable to find the Joker. Clark tells him that he is concerned about his relationship with Lois. Bruce assures him that he is taking her quite seriously. Lois returns and the two head off.
Later after dinner, Bruce and Lois talk about Clark Kent when they are interrupted by the Joker. The Joker grabs Lois and knocks her out. The Joker's gang starts to shoot at Bruce who falls backward off a ledge. He lands on a window washer platform. The Jokers men shoot the platform out from under him. Bruce falls, but manages to grab a ledge. He looks up and sees the Joker escaping in a blimp.
Later Dan Turpin interviews Bruce Wayne. He tells Bruce that the SCU will recover Lois. After Turpin leaves, Bruce tells Superman that the Joker is using Lois as bait. Superman tells him that he will keep his eyes open and flies off.
Meanwhile, the Joker and Harley hold Lois captive. The Joker tells her about his Kryptonite statue and how he is going to use it to kill Superman.
In an airport hanger, Alfred watches as a Jumbo Jet opens revealing the Batwing. It flies off. At SCU headquarters, Dan Turpin and Superman receive a message from the Joker. The Joker tells Superman that he has Lois. He shows Superman a map to his location and tells him to come alone. Superman heads out to deal with the Joker by himself. Meanwhile, Batman observes Superman's flight in the Batwing.
Later, Superman arrives at a LexCorp laboratory wearing a suit designed to protect him from Kryptonite. Superman confronts the Joker and after a brief exchange, the Joker pulls out some Kryptonite. The suit protects Superman from any harmful effects and he takes the Joker prisoner. The Joker leads Superman to a room where they see Lois suspended from a hook high above the ground. The Joker bemoans the failure of his plan, but suddenly remembers the other half of it. He douses Superman with acid and tosses the Kryptonite at him. Superman falls and the Joker attacks him. As Superman lays dying, the Joker dances around in pleasure. He zaps Superman with electricity and taunts the helpless Lois.
In another part of the building Batman arrives. Unfortunately he is spotted by Harley Quinn. Harley tells the Joker that Batman has arrived. The Joker wishes Lois farewell and heads off.
After a short fight, Batman deals with the Joker's gang. He heads into the room with Superman and Lois. He grabs the Kryptonite, but when he turns to take it out of the room, the door locks. A television turns on revealing the Joker. He mocks Batman as the room begins to fill with Smilex gas. Batman examines the contents of the room. He sees that it contains hydrochloric acid. It is not enough to eat through the wall, but Superman tells him to use it on the Kryptonite. Batman pours the acid over the Kryptonite and it slowly dissolves away. Superman makes it to his feet. He grabs Lois and Batman and breaks through the door.
In the control room, Joker and Harley realize that Superman has escaped. Superman breaks into the control room, but the Joker throws a bag full of marble grenades to cover his escape. Superman, Batman, and Lois escape from the building and set down in a parking lot. Superman thanks Batman and Batman heads with the help of the Batwing.
After Batman leaves, Lois asks Superman whether Bruce Wayne is okay. Superman tells her that he is perfectly fine.
The next day, Lex Luthor is at the remains of the LexCorp building blown up by the Joker. He tells reporters that the explosion was not nuclear. He heads off with Mercy and whispers to her his dissatisfaction with the Joker. Clark using his super-hearing manages to overhear him. At their secret hideout, Harley tries to cheer up the Joker (Harley Quinn: (waving a gingerbread man around) Hello, Mr. J! I'm Batman! Eat me, eat me, eat me!
The Joker: I know you're trying to cheer me up, Harley, but you see, any time I blow a billion dollar deal... IT REALLY KILLS MY APPETITE!!
). Suddenly, they are attacked with machine gun fire. It is Lex and Mercy. The Joker tries to apologize to Luthor, but Luthor (angry that one of his laboratories was destroyed) grabs him. Joker calls to Harley and Luthor calls for Mercy. The two girls fight while Luthor and the Joker iron out their differences. The Joker tells Luthor that Batman ruined his plan. He tells Luthor that he still has half the statue and that he can finish the job. He demands more money to deal with both Superman and Batman, but Luthor refuses. The deal is still on, but the Joker is not going to get any more money. Luthor and Mercy leave after Luthor tells the Joker that he only has one more chance. Later at Lois's apartment, Clark Kent arrives and is invited in. He is surprised to find Bruce Wayne there. Clark tells Lois and Bruce that the Joker is working for Lex. That night in Lex's penthouse, Batman arrives asking for information. He asks about the Joker, but Luthor refuses to talk. Batman heads off when Luthor's security arrives. When the security men enter Luthor orders them to leave. Luthor tells Mercy to contact the Joker. He now wants to have Batman eliminated.
At the Daily Planet, Lois tells Clark that she is interested in transferring to Gotham City. Perry White arrives and tells them that the cruise ship Atlantis is giving off a distress signal two hundred miles off shore. As Lois sits down to check the information, Clark turns into Superman and heads off. Bruce Wayne is working out in his apartment when he spots the Joker's blimp. On the blimp is a sign that reads "Laff Night at Hobbs Bay". Bruce gets the message and using a power glider, he heads off to the bay.
Superman arrives at the cruise ship and asks the captain about the distress call. The captain doesn't know what he is talking about. Superman looks over the side of the ship and spots a small boat sending off a distress signal. The small explodes, blowing a hole in the side of the ship. Meanwhile, Batman arrives at the bay and is greeted by the Joker and a laser-equipped LexCorp Spider robot. Batman arrives via glider at Metropolis Harbor. He is met by the Joker and a LexCrop Spider Bot. Meanwhile, Superman uses a lifeboat to weld over the whole in the side of the cruise ship. At the harbor, Batman engages as Spider Bot. The Joker escapes while the robot pursues Batman into the streets Metropolis. Eventual Batman arrives at the Daily Planet looking for Clarke. He finds only Lois. The Spider Bot soon arrives and attacks Batman. Eventually, with the help of Lois, Batman sends the robot into a printing pres. Batman, however, is unmasked in the process. Lois sees that Batman is really Bruce Wayne. Before she can have words with him, the Spider Bot attack them again. Superman, however, arrives in time to save them. At LexCorp Headquarters, Luthor realizes that wreckage from the Spider Robot can be traced to him. He tells Mercy to arrange a final meeting with the Joker. At her apartment, Lois tends to Bruce's wounds. She expresses her frustration at him over his secret identity. As Lois heads out for some iodine, Superman arrives. Bruce thanks Superman for saving him. Bruce says that he can link the robot to Luthor. The two agree to a partnership. When Lois returns, Bruce is suiting up as Batman and is preparing to leave. He leaves before she can tell him to be careful.
Meanwhile at LexCorp, Joker and Luthor discuss business. Luthor wants Joker's Kryptonite. When Harley reveals that they brought it, Mercy pulls a gun on them. Luthor plans to pin the wrap wholly on the Joker. Unfortunately, the Joker turns the tables on him. He knocks Mercy out and Harley takes the gun. The Joker kidnaps Luthor and steals a powerful LexCorp flying wing. Superman and Batman arrive and enter Lex's building. The Joker activates several Spider Robots as a distraction. He sends them after Batman and Superman and takes off in the flying wing. After a short fight, Superman and Batman manage to dispose of the Spider Robots. They manage to free Mercy who was tied up to one of the machines. She tells them that the Joker has kidnapped Lex and that he wants to destroy everything that Lex has ever built. Superman is worried when he realizes that Lex built half of Metropolis. Batman heads off to stop the Joker while Superman stays behind to deal with the final spider robot. Meanwhile over the city, the Joker attacks LexCorp buildings throughout Metropolis. Eventually Batman arrives and engages them in the Batwing. Using the LexWing's missiles, the Joker shoots Batman out of the sky. Batman manages to escape and jumps onboard the LexWing.
At the same time, Superman fights off the Spider robot even after it exposes him to Kryptonite. Using a lead lined door Superman smashes the robot and sends it flying right out of the building. The Joker continues to attack the city when Batman attacks him and knocks him off of the controls. Harley takes over and begins to crash the aircraft. Superman arrives just in time to stop the ship from crashing. The Joker and Batman fight until the Joker reaches for his exploding marbles. He drops the bag causing small explosions all over the ship. Batman grabs Harley and Superman grabs Lex. The two of them escape the LexWing before it explodes. The Joker attempts to get a parachute. Unfortunately the LexWing tilts and knocks him to the ground. He sees the exploding marbles heading his way and he laughs hysterically. After a few moments, the LexWing explodes and crashes into the ocean. Superman flies over and grabs Batman and Harley. They head back to the city with Lex in tow. Later, Angela Chen reports that the Joker's body has not been found. She also reports that the D.A.'s office has been questioning Lex over his connection with the Joker's rampage. She also announces that Bruce Wayne has cancelled his partnership with LexCorp and that Harley is being taken back to Arkham Asylum (her words were i want a dr. a lawyer a grilled cheese sandwich, mercy watching news laughs & said now thats funney ). At the airport, Bruce and Lois talk. She tells him that she can't go with him and heads off. As he heads to the plane, Bruce runs into Clark. Bruce wishes him good luck with Lois and heads off.