Zim gets a pimple after GIR rubs pizza grease all over his face. When he applies acne cream to it, it swells into giant, pus-filled water balloon. Initially embarrassed, he discovers that it has hypnotic powers when he bounces it up and down. Disguising it as a little friend dubbed "Pusstulio", Zim hypnotizes the entire skool to do his bidding and manages to get some secrets out of Dib in the process.
"Rise of the Zitboy" contains examples of:
- Accent Upon The Wrong Syllable: The pizza delivery guy to GIR: "Here's the pizza ya' or-DERED."
- Artistic License – Biology: Invoked for comedy. Dib looks away from Zim's pimple to avoid getting hypnotized, but Zim tells him that he'll open them eventually because he'll eventually need to breathe. Dib wonders what his eyes have to do with breathing. This distracts Dib long enough for Zim to hypnotize him.
- The Bad Guy Wins: Zim successfully manages to mind control Dib into revealing flaws in his base's defenses that only Dib knows about so that he can fix those flaws and gets away with mind controlling all of the students.
- Bizarre Alien Biology: Zim is apparently capable of getting acne, but applying Earth acne cream to it causes it to swell until he looks like he has two heads. In the end, it gets big enough to fill the entire classroom at skool, and it spews fire hose-pressure pus when it bursts.
- Bread, Eggs, Milk, Squick: Zim gets the body he attaches to his pimple out of a box in his storage unit labeled "Gears, circuits, headless bodies."
- Extreme Omnivore: GIR consumes an entire pizza, then drinks the zit cream that he offers to Zim.
- Instantly Proven Wrong: When Dib leaves after failing to infiltrate Zim's house, Zim brags that nothing will ever breach his defenses. On cue, a deliveryman from Bloaty's Pizza Hog arrives and effortlessly walks past Zim to hand GIR a pizza.
- Hypnotic Head: Pusstulio is just Zim's enormous zit with a face drawn on it and a little puppet body attached to the bottom.
- Hypnotism Reversal: Zim is briefly entranced by his own zit when he looks into a mirror, but he is quick to shake it off.
- Karma Houdini: Zim gets away with mind controlling many of the skool students with "Pusstulio" and inadvertently making a huge mess in the skool with his pimple burst.
- Kick the Dog: After Zim hypnotizes him into revealing a blind spot in his house's defenses, Dib is forced to clean up the river of pus left behind by Zim's burst pimple... with 1/5th of a sponge.
- O.O.C. Is Serious Business: Zim first realizes the hypnotic power of his zit when the normally disobedient GIR, under it's control, says he will obey him.
- Mass Hypnosis: Zim uses Pusstulio to hypnotize the entire skool to do his bidding.
- Shout-Out: Gaz is seen reading Punch Club.
- What Happened to the Mouse?: The episode begins with Zim firing chickens into the sun. It never comes up again once the plot kicks in.
