Oscar decides he’s going to mess up Sesame Street. He changes into his uniform and starts a new company with two other Grouches, Hiram and Burt. Their new company, Dirtballs, specializes in dirt and is going to transform Sesame Street from one of the cleanest streets into one of the dirtiest. Their first stop is the garden. With a blow of Oscar’s whistle, the group dumps dirt all over. Luis is happy because they just ran out of dirt for planting! Next, the Dirtballs dump dirt outside Hooper’s Store to mess it up. However, it solves Chris’ problem of where to keep Willie, the hamster he’s taking care of. The new dirt pile is a perfect home for him to burrow in! Next, Dirtballs stops by the Laundromat to make all of the clean laundry filthy. Leela and Baby Bear are looking for a new game to play and Oscar’s dirt turns out to be perfect to play “Buried Treasure.” They dig in the dirt and find all kinds of hidden treasures, such as leaves, twigs, an acorn, a bone, and earthworms. Bert even finds a rare bottle cap to add to his collection. Dirtballs messing up Sesame Street turns out to be a great idea!