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Rats, like pigs, are the all-purpose utility players in Muppet productions. Apart from just hanging around and being rat-like, these rodents have often taken on specific collective roles or portrayals. Some are traditional to the species, while others cast them against type.

Picture	Role	Production	Notes
	Bellhops	The Great Muppet Caper	The rats are employed at the Happiness Hotel. Rizzo the Rat is the lead bellhop.
	Waiters/kitchen staff	The Muppets Take Manhattan	Rizzo works at Pete's Luncheonette and later brings in Yolanda, Tatooey, Chester, and Masterson. When customers complain about rats bringing the food, Pete has them cook and wash dishes instead.
	Bookkeepers	The Muppet Christmas Carol	The rats serve as Scrooge's bookkeeping staff, with non-rat Bob Cratchit as chief clerk.
	Tourists	Muppet Treasure Island	Rizzo books the Hispaniola as a cruise ship to his fellow rodents. Only Mr. Plagueman is named.
	Surf Rats	Muppet Beach Party	The rats are heard but not seen as a group of beach fanciers who provide backing vocals.
	Stage crew	Muppet Classic Theater	Rats oversee the lights, props, curtain, and other technical aspects.
	The Rats' Patrol	Muppets Tonight episode 104	WWII era soldiers fighting the enemy cheese under the command of their human Sarge. Includes Rizzo and Indiana.
	Lab rats	Muppets From Space	Test subjects at the C.O.V.N.E.T. laboratories. Rizzo is introduced to the inmates: Bubba, Fast Eddie, The Birdman, Troy, and Shakes.
	Munchkins	The Muppets' Wizard of Oz	The cheerful, tiny, cute residents of Munchkinland who are not rats at all. Rizzo serves as their leader, and Bubba also appears.