Boog is having a yard sale outside the Frosty Mart, inflating helium balloons to decorate. Fanboy and Chum Chum come across a large plastic bubble, which Boog explains is from his childhood, when he had many allergies. The boys buy it from him and go off to play with it, bouncing recklessly around town.
When they try to get a Frosty Freezy Freeze while still in the bubble, though, they cause an accident which destroys the money Boog made at the yard sale and breaks the Chimp Chomp machine. Furious, Boog tries to bop the boys, but finds that while they're in the bubble he can't hurt them. But he then points out that since they don't have the bubble's toilet attachment, they'll eventually have to come out. He then sits with them and waits.
Having fallen asleep at some point, Fanboy and Chum Chum wake up at night time and find no sign of Boog. They leave the bubble to use the bathroom and then get some food in the store.
But when Boog sneaks up and tries to attack, the boys manage to escape back into the bubble. Boog then pretends to have an allergy attack, tricking the boys into letting him in the bubble. As he then prepares to attack, and Fanboy and Chum Chum back away, they end up outside backing the bubble into the balloon helium machine from the yard sale. The nozzle pierces the plastic bubble and lets helium inside. Fanboy and Chum Chum can't help laughing at how high-pitched they and Boog sound, and Boog is taken off guard. Fanboy and Chum Chum get out of the bubble and use the helium to send it flying with Boog still inside. Boog lands in a tree, where he complains that he's allergic to a nearby squirrel.
Tropes:
- Camera Abuse: While testing out the bubble, Chum Chum slams it into the screen.
- Deus ex Machina: the helium machine.
- Helium Speech: Fanboy, Chum Chum, and Boog.
- Iris Out: The episode ends as the iris out focuses on the boys, then bounces away.
- Self-Induced Allergic Reaction/Save the Villain: Boog fakes an allergic reaction to breathing air so Fanboy and Chum Chum will let him inside their plastic bubble. The two fall for it, and immediately afterwards, Boog's allergy clears up and he proceeds to beating up Fanboy and Chum Chum.
