The next day at the Powerpuff Girl's house, the Powerpuff Girls and Professor Utonium are trying to find out what the Joker and Mojo Jojo are really up to. "What would Mojo Jojo be planning with the Joker." Says Blossom. The Professor is reading the newspaper. "The Powerpuff Girls are not the only ones who saved Ms. Bellum. Townsville's new vigilante, Batman, teamed up with the girls." Buttercup glares at the Professor, who nervously smiles. "Looks like you three and Batman make good teamwork together." "Sorry," says Bubbles, "we're not really in the mood for that." The girls then fly off to Pokey Oaks Kindergarten School.
Meanwhile in Mojo Jojo's observatory, the Joker and Mojo are arguing over their failure last night. "Taking down Batman was a project of mine." Says the Joker. "And those miserable Powerpuff girls are always in my way of taking over the world." Says Mojo. "I have had a lot of schemes back in Gotham and guess what." Says the Joker, "That Bat-Breath shows up and spoils them all." "Well we'll have to do something to forever destroy him and those three brats." Says Mojo. Harley walks by and says, "I know one way to take them all down Puddin'." "And what would that be?" asks the Joker. "How about we use some kind of battle robots to destroy them." "Say Harl," says the Joker, "That sounds like an excellent idea." He then turns to Mojo and says, "We still have half of that Chemical X. We can use them in battle robots." Mojo thinks for a moment and says, "Very well, I do have several technology we can use to battle against them."
Later that afternoon, the jewelry store is being robbed. The thieves are getting away, but of course the Powerpuff girls arrived just in time to stop them. They pummel them and the jewelries are safely returned. They then return to their home. "Professor," says Blossom, "we should continue our…" But they were distracted by the sight of Bruce Wayne sitting in the living room. "Bruce Wayne?" says Bubbles. "What do you think you are doing in our house?" asks Buttercup demandingly. "Well I wanted to talk to your dad about some important things." Says Bruce, "Is that a problem?" The Professor comes in and giggles, "I am pretty sure we are enjoying our discussion." He says, "Now Bruce how long did you say you worked at Wayne Enterprises?" "Well I took the leading chair after the passing of my father." Says Bruce. "What does that produce?" "It produces WayneTech, which retrieves and researches on alien technology." "Amazing," says the Professor, "Do you like that job?" "I do." Says Bruce. The girls fly into the living room. "Have you had any corruptions in that business?" asks Blossom. "Wayne Enterprises rival against LexCorp, an enterprises in Metropolis." "Mr. Wayne," says the Professor, "are you aware about the Joker and Mojo Jojo planning something sinister?" "Well," says Bruce, "They captured Ms. Bellum last night." "And we and Batman saved her." Says Buttercup. "Batman?" asks the Professor, "Who is Batman?" "Oh he is a vigilante who always stops crime in Gotham." Says Bruce. "Apparently he followed the Joker here to stop him." Says Bubbles, "And we must stop him and Mojo Jojo from taking over the world." "Well," says Bruce, "You girls take care of all that." As he leaves for the door, girls look at him secretly.
Later that night at the Mayor's office, the Mayor and Ms. Bellum are sitting on the couch. "Ms. Bellum," says the Mayor, "Are you and Mr. Wayne in a serious relationship?" "Looks like." Says Ms. Bellum, "He asked me to move to Gotham with him." "Move to Gotham City?!" gasps the Mayor, "But who will be my new secretary?" At that moment, an explosion blows up the walls. It is a robot built by Mojo Jojo. Ms. Bellum and the Mayor run for the door, but another robot breaks through it, barging their escape. The robots have monitors where the Joker and Mojo Jojo are watching from the observatory. "Now time to get rid of the Mayor." Says the Joker. The robot blasts at the Mayor, who runs away in cowardice. As he tries to hide, Ms. Bellum takes the Powerpuff Hotline and calls the Powerpuff Girls. Blossom answers it and says, "Hello? We're on our way." They fly to the Mayor's Office in time to take on the robots. Blossom spins around the room, distracting who of the robots while Bubbles and Buttercup take on the other. "Wahahaha!" laughs Mojo, "These Powerpuff girls shall meet their demise!" Bubbles dodges a grapple arm, then she punches through it. Buttercup then uses her heat vision to damage the robots sensors. Then together, she and Bubbles knock it over, destroying it. "Good work Buttercup!" cheers Bubble. "Now it's not the time for victory Bubbles." Says Buttercup, flying over to help Blossom. Blossom uses her ice breath and freezes the other robot. Next Bubbles fly kicks and knocks out the robots armed gun. Then Buttercup uses her heat vision to melt the robot's frozen body. But the robot's head comes out and walks towards the girls. Batman arrives just in time to smash it whole. "Did I miss anything?" asks Batman. At that moment, the ceiling crashes down. It is a third robot. "It's time to die!" says the Joker. "Say goodbye!" says Mojo. The robot approaches the heroes. Batman throws a batarang at it, provoking the robot to attack him. Batman and the Powerpuff girls fight the robot while Ms. Bellum helps the Mayor. "Go," she says, "I'll help Batman and the girls. The robot blasts Blossom, but Bubbles fires her laser at it. As the robot fights Bubbles, Batman uses his grapple gun to lure it away. The robot hits Batman with its grapple arm, causing the mask to fall off. Ms. Bellum could see that Batman is in fact Bruce Wayne. "Bruce?" she exclaims. Buttercup dismantles the robot's arm off. Then Batman throws a gadget at the robot. It manually shut it down. "Hooray!" cheers the girls. As Batman puts his mask back on, Ms. Bellum comes by. "You okay Ms.?" Asks Batman. "Drop the act." Says Ms. Bellum, "I know your secret."