Later at Ms. Bellum's house, Ms. Bellum is bandaging Bruce's gash on his back. "I can't believe you kept this secret from me." Says Ms. Bellum. "Well now you know it." Says Bruce with a chuckle. Ms. Bellum slaps him on the back near the gash. "Ow!" he cries. "You don't get to joke!" snaps Ms. Bellum. "Sorry." Says Bruce. The Powerpuff girls show up. "What do you think they are up to?" asks Blossom. "I suppose they are at their secret lair." Says Bruce, "And I suppose that you three might know the whereabouts." "Of course we know." Says Blossom. "Stay here," says Ms. Bellum, "I'm going to get some liquid to heal that cut." She walks over to her supply cabinet. But when she comes back, Bruce Wayne is gone. The window is open with curtains flapping in the breeze.
At the observatory, Mojo Jojo leads the Joker and Harley Quinn to a big laboratory. "And these are my greatest creations." Behind the glass are big robots with the most lethal weapons. "Wow!" says the Joker, "This is so marvelous!" "Correct," says Mojo, "I am smart in all of those ways. When Professor Utonium accidently added the Chemical X, it caused my brain to mutate and grow and at the same time increasing my intelligence." The Joker and Harley Quinn then go over to something behind glass. They look at a huge ship. "Why!" he says, "This is way better than Batman's Batmobile." "Ooh I want to ride it!" says Harley. "That's right," says Mojo, "and there's something else I want to show you." He takes out a device and activates it. This activates some hidden cannons. "I have fueled those with the remaining half of the Chemical X." he says, "With the robots and the cannons, those heroes will stand no chance in my plan on taking over the world." "That's a marvelous plan." Says the Joker, "But I believe that we have a much better consolation prize." He is planning on using the big ship.
Meanwhile the Batmobile arrives at the observatory. Batman and the girls hop out of it and heads over to it. Batman looks up at the observatory and says, "It's too high, it's gonna take a while to get up there." "Oh no we're not," says Blossom as she, Bubbles, and Buttercup carry him up to the top in a jiffy. "We're super-fast in speed." They all enter the observatory. They start to search for the Joker and Mojo Jojo. Bubbles sees a sign reading, "to the secret lab." "I think they're down there." She says. They go down to the room, unaware that they are being monitored by the Joker, Harley Quinn, and Mojo Jojo on a surveillance camera. They are on the ship. "Ooh this is going to be real funny." Says Harley Quinn. Batman and the Powerpuff Girls are looking around the lab. "What do you think they are up to?" Bubbles asks Buttercup. "I bet they are baiting us. But I'm ready whenever they are ready." "As you wish." Says the Joker as he activates a button on the ship. Immediately the robots behind glass turn on and break through them and the cannons come out and activate. "Looks like you three will have to back me up." Says Batman as a giant robot approaches him.
Meanwhile the Joker, Harley, and Mojo are taking off. The ship hovers into the air. "Now let's see what it will look like to destroy this town once and for all." Says the Joker. "This is what I have dreamed of for years." Says Mojo. He presses a button, activating machine guns on the ship. Meanwhile Batman throws some batarangs at a robot, but to no avail. The robot starts to shoot lasers at him, who quickly evades them. Blossom flies from a robot who is trying to grab her with its grapple arm. She flies around the robot, causing the grapple beam to wrap around it. Then it falls to the ground. Batman is facing the other robot, who gets ready to fire a beam at him. But Batman throws a batarang at the robots laser gun, causing it to fire at the robot tied to the ground, destroying it. Buttercup cheers for that. But then gets blasted by the robot with the laser gun. "Buttercup!" cries Bubbles.
Meanwhile the Joker and Mojo Jojo are laughing maniacally as Mojo fires missiles at multiple buildings, causing chaos and destruction throughout Townsville. "This is the moment that really puts a smile on my face." Says the Joker. Meanwhile Buttercup and Bubbles are facing the robot, who fires a laser beam at them. As they fly past it, Batman uses his grapple gun to lure it away. This allows Buttercup to use her heat vision to destroy the robot laser gun. Then Bubbles flies into it and out, knocking out the main power core in the process. The robot falls down destroyed. But then another robot shows itself. Blossom comes in and blows her ice breath at it, freezing it. Then Batman throws a bomb at it, destroying it in an explosion. "Yahoo!" cheers Buttercup, "We kick robot butt!" But just then, the Chemical X canons appear and start firing blasts at them. They all dodge the blasts. "Bubbles, Buttercup you take care of those cannons." Says Blossom, "Batman we're going after the Joker and Mojo Jojo."
As Bubbles and Buttercup handle the cannons firing Chemical X, Blossom and Batman head out of the observatory to find the Joker and Mojo Jojo. "Where do you think they are?" asks Blossom. Batman could hear blasting noises and could see people running for their lives. And he could see the ship in the air. "In the pilot." Says Batman. He activates his flying contraption and flies over to the ship along with Blossom.