When the kids learn that they can't go to the real circus, they use their imaginations to play pretend circus. They become elephants and tumblers. They even imagine Grampu as a juggling, hilarious clown. — ABC Television (source)
The episode starts in Oobi and Uma's room, where they have a poster advertising a circus show. The kids spot an elephant on it and pretend to be elephants together. Uma invites the viewers to pretend along with them, and Kako says he'd like to be a circus ringmaster. Oobi adds that he loves the circus because of all the talented acrobats. Uma tells the boys that her favorite part of a circus is the elephants.
The kids ask Grampu if they can go to the circus, but he tells them that it's too far away. The kids are disappointed at first, but Kako gets the idea to make a pretend circus. He brings over a hula hoop and calls it the "circus ring." He hovers the circus ring over Oobi and Uma, and they find themselves at a cool pretend circus with Kako as the ringmaster. He introduces a crowd to Oobi and Uma, who act as acrobats by jumping, flipping, and hopping on top of each other. After their act, they bow to the audience and ask the viewers to bow along with them.
After that, Uma pretends to be an elephant and Oobi wears a peanut costume. Uma chases Oobi until Kako introduces the next act: Grampu as a clown. Grampu says his clown catchphrase, "Oopa-doo!", and tries to juggle a ball. He later balances the ball and a flower on his nose. He finishes the act by picking up a pie and balancing it. When he takes a bow, he ends up landing face first in the pie.
Kako says goodnight to the pretend audience, and the kids finish their circus act. Grampu calls them to the kitchen for lunch, and Kako lifts up the circus ring. They end up back in Oobi's room. Oobi says the circus was amazing, and Uma wants to say so too, but she has trouble pronouncing the word. After getting a little help, Grampu calls them to kitchen again. He gives them peanut butter sandwiches for lunch and pie for dessert.
The pie reminds the kids of their circus, so they start chanting "Oopa-doo!" and invite the viewers to join them. Grampu is confused but goes along with it anyway. Afterwards, Uma appears in the interview segments, asking preschoolers if they've ever visited the circus. The episode ends with a stop-go game hosted by Kako. Halfway through, Grampu comes in as a clown, and the kids laugh with him.