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. 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.