Sheldon J. Plankton founded the Chum Bucket shortly after ending his friendship with Mr. Krabs. Since then, Krabs has become his arch-nemesis and the owner of a much-more successful restaurant, the Krusty Krab. Plankton's ultimate goal is to take the secret recipe of the Krabby Patty and sell the food at his own restaurant. His computer sidekick Karen has the ability to analyze the ingredients of a patty, but so far, Plankton has never successfully retrieved one.
The Chum Bucket is located directly across the street from the Krusty Krab.
Plankton is part of a long line of evil planktonic organisms. His earliest known ancestors are from the Middle Ages: Planktonamor the Wizard and Karen the Crystal Ball. He has over 10,000 living relatives, mostly hillbillies.