It's Halloween and the entire town is getting into the Halloween spirit; much to Zim's dismay because he considers the entire concept to be insane and he doesn't want filthy Earth children coming to his house. Meanwhile, Ms. Bitters sends Dib to an insane asylum because he has been acting crazier than normal, in which in truth he has been getting sucked into a nightmare world that was created due to his meddling with one of his father's inventions. After finally getting out of the nightmare world and out of the insane asylum, Dib sees Zim's house and decides to force Zim to come with him into the Nightmare world because he believes Zim will have the capability to put an end to all the madness, but will they manage to work together despite the fact that they're enemies and that Zim didn't want to help him in the first place?

Professor Membrane has just unveiled a world changing machine that will completely remove the entire need for fuel, though if the machine were to malfunction, it could cause a giant shockwave that would destroy all life on Earth. However, Professor Membrane refuses to turn the machine on until his children are present, in which Dib is absent because he is attempting to prevent Zim from sabotaging the machine. However, things soon take a turn for the worse as Dib falls into one of Zim's traps and the crowd in front of Professor Membrane beings to grow uneasy over the fact that they've waited so long, so Professor Membrane decides to send Gaz to go find Dib and put an end to his foolishness.