Lilo tries to clean Pudge's grotto for Earth Day, but meets an experiment that eats trash and later redistributes it across the island as pollutant goo. When Stitch gets sick from eating trash, Jumba and Pleakley have to find a way to cure him, and Lilo must find a way to stop Ploot by herself. She tries enlisting other experiments to help (first Kixx, Deforestator and Richter; later Finder, Babyfier and Drowsy), but Ploot is too powerful for them. Eventually, Stitch is cured and thanks to Pleakley, a way to defeat Ploot is found through a combination of air fresheners. With help from Stitch, Lilo defeats Ploot herself, and he becomes good and sets to work at cleaning up trash and pollution rather than making it.
- In his debut, Ploot is erroneously called 515, a number taken by Deforestator, who ironically appears in this episode as well.
- When Richter throws Kixx toward Ploot, Richter's underbelly is purple instead of lavender.
- In some shots, there is nothing on Deforestator's back, but in one scene when Ploot defeats them, markings and a tail appear on Deforestator's back.
- Moral: Everyone can make a difference.
- Pudge was mentioned by Lilo in this episode.
- This episode was aired on Earth Day.
- This is one of three episodes where Stitch's fur becomes a different color, the other two being "Houdini" and "Swapper".
- It is revealed that if Stitch consumes vast amounts of trash, he will become incredibly sick.
- Stitch first got sick to his stomach and sneezed as his fur turned yellow and developed an orange tongue and red nose. After each sneeze, an arm also grew from different parts of his body, while Jumba theorized Stitch's garbage-eating illness as a rare space disease.
- After Stitch drank a barrel of orange juice and took medicine from an eyedropper, he was only temporarily cured. When he sneezed again, he developed yellow stripes and grew legs instead. Inhaling steam from a vaporizer permanently got rid of his sickness, though.
- According to Lilo, she has never caught an experiment alone until she successfully captures Ploot by herself.
- It is unclear why Sparky would need to stay at the lighthouse, since it was daytime.