This episode starts out going up to the Megadoomer Combat Stealth Mech. Purple said that he doesn't like it, and Red told him that they didn't build it so he could like it, it's going to Planet Meekrob to help Invader Tenn conquer it, and Purple said that he should like then. They go up and see various malfunctioning SIR units. Purple said that they were dangerous, and to send them to Zim, and Red, sarcastically, said that they'll destroy him. They started laughing and Purple said lets go eat food.
On Conveyor Belt Planet, a native is rambling on about how the Irks enslaved their people and how he is going to rebel. He decides to switch the adresses on the two giant boxes, sending the Megadoomer to Zim and the malfunctioning SIR units to Tenn. He's talking about the revolution, when he is zapped by and Irken Guard.
On Earth, Zim is walking home, talking to a kid about how filthy and squirmy Dib is, and the kid he was talking to asked what he was talking about and who he was. Zim is rambling on again, and the kid asked why he was following him, he doesn't even go to his school. Zim, once again, rambles on some more, and they kid runs into a house. Zim follow him, but doesn't go in, saying in mocking voice, "My name is Dib and I have pointy hair, POINTY HAIR!, and I eat food..."
Zim makes it home, and in the doorway he says that he will pay. Right when he closes the door, the box with the Megadoomer falls from the sky and lands in his yard.
Zim calls the tallest, saying that they've done the right thing and some other stuff, but I don't know what he was saying because he was talking really, really fast, and signs off. Tenn calls in and tells them that it's horrible, and her camera switches over to the malfunctioning SIR units.
Back on Earth, Zim is telling GIR about the megadoomer. Zim tells him that it has a Distortion Cloaking System, and asked if he knew what that meant, and GIR goes crazy for two seconds. Zim tells him that it can turn invisible, and GIR said that he had no idea. Zim stands on GIR and he brings him up to the cockpit. He says that it's a bit much, be he will use it on Dib. He gets in and starts pressing buttons, but nothing is working. GIR pulls out something, and Zim notices that it doesn't have any batteries, so he plugs it into the wall. Zim breaks out of his house, and GIR is pulling the power cord along with him. Zim tells him to be careful with the power cord, and even though he can't see him with his cloacking device on, he can follow the sound of the stomping. Zim is walking down the street with his cloacking on (they can still see Zim sitting there, but they can't see the robot), and everyone is a little freaked out. The power cord comes unplugged, and the cloak comes off. Zim asked GIR what had happened, and he tells him that it isn't plugged, and he told him to find another outlet. GIR carries the giant plug around until he sees a lit up pig in the yard, kicks it off, and plugs the plug into the outlet.
Zim is rounding a corner when a cop pulls up and tries to shoot Zim, but the bullets are blocked, and Zim smashes the cop car. It comes unplugged again, and GIR goes and plugs it in at an old folks home. Once he plugs it in, he starts break dancing, and the old people are completly oblivious to this.
Little kids are playing in a sandbox with robot toys, when Zim comes up by them and the plug is unplugged again. GIR plugs it in again and Zim gets moving, and GIR comes and takes the kids' robots away from them and eats them.
Dib is brushing his teeth, when he sees the water in the toilet move. He looks out the window, and hears Zim tell Dib to prepare for the end. He runs outside and sees Zim sitting there, and Zim tells him that he's put up with him long enough, and to prepare to face an enemy he cannot see. Dib tells him that he's right there, and the mighty Irken cloaking device cloaks the robot but not him. Zim tells him it's a lie, and to behold the doom cannon. Dib said he can't, and Zim asked if Dib could see him, and he said yeah, and Zim said that was stupid. He told him to prepare for his doom, and started pressing buttons. The computed said that a power draw was critical, and all the power to the city went out and the cloak came off of the robot. Dib took thousands of pictures, saying that Crop Circle magazine was going to put him on the cover, and he told GIR to take a picture of him standing next to it. Zim told GIR to stop, and when he wouldn't, he turned on the self-destruct, which spit him out. The robot exploded and Zim took the camera from Dib and screamed victory. Dib told him that his robot exploded and he didn't destroy him, and Zim told thim that his plan was to steal the camera so he couldn't expose him, Dib took the camera away from him after a little fight for it. Zim tells Dib that he had the lense cap on, and ran. He stopped, turned around and said victory for him, but a piece of the robot fell on him. A vulture came and took the camera from Dib, and he said that he liked that camera, but he guessed that was a victory for him, and said he was going to bed.
The tallests got a reading that the Megadoomer self-destructed, and Purple asked if Zim was in it, and Red said probably not. Tenn came on, saying that the SIRs have eaten everything, and they're all doomed. The tallests just sat there and watched in horrer.