When Homer costs a carnival worker and his son their jobs, Homer offers the pair a place to stay. But when the carnies lock the family out of their house and claim it as their own, Homer attempts (successfully) to get it back by outsmarting the two.
Marge goes into the backyard and orders the kids to clean it but Bart and Lisa refuse to. Marge chucks them out there but the kids quit which Marge says the get no allowance if they don't clean but Bart and Lisa don't care because the get their board and room for free anyway. The carnival comes into town and the family is all excited over it. Among the attractions is a car which was supposedly Hitler's presidential limousine. Bart decides to sit in it, but he accidentally engages the clutch and crashes it into a tree, enraging the carnival owner.
To pay for the damage Bart has caused, Bart must work of his debt as a carny, which gets Bart excited and Homer wanting to be a carny too. At their first day, they learn that being a carny is not fun, as it involves jobs such as cleaning up after horses. There they meet Cooder and Spud, two carnies who run the ring toss booth. When Cooder and Spud have to leave for their AA meeting, they put Homer and Bart in charge of their game, showing that it is rigged (which Homer doesn't believe and pays to play). When Chief Wiggum comes by looking for a bribe, no matter how clear and obvious his intentions are (even saying he's looking for a 'Mr Bribe') Homer doesn't get it, so Wiggum shuts down the game and takes it away. The booth also happened to be Cooder and Spud's residence so Homer invites them to live with him. Cooder gives them tickets to a glass-bottom floor boat tour, but then when they return, Cooder and Spud have boarded up the Simpson residence and are now illegally squatting in it.
The Simpsons are forced to live in the treehouse and they plot a way to get their house back. Homer comes up with an idea to beat them at their own game. Homer lures Cooder and Spud outside, challenging them to a game where he will attempt to throw a hula hoop over the chimney. If he misses he'll sign the deed over to them, but if he makes the shot, Cooder must give the house back. Just when Homer is about to throw, he and the family run into the house and trap the Cooders outside. Now settled in their home, Homer proceeds to fix his couch "groove" that Cooder has messed up.