The Sickening Fumes of Smartsy Fartsy is the twelfth episode of The Epic Tales of Captain Underpants.
Pulling too many pranks has got George and Harold one step closer to being expelled, so they use Melvin's new machine (which was made so Melvin could steal George and Harold's idea of living gas) to bring George's fart to life so it could get into Mr. Krupp's safe so they could get it to Vil Endenemys and he'd be fired. However, upon reading their new comic book, Smartsy Fartsy (George's fart) became offended and rebelled against George and Harold so the he could give all of gaskind some respect.
- The Tomorrow Talk is a parody of TED Talk.
- Moral: Everybody deserves a little respect.
- This is the first episode Mr. Krupp and Captain Underpants have long hair.
- Mr. Krupp thinks that one of Harold and George's gases smell like a dog eating a diaper.