Buster is coming home and Arthur is excited. He is also afraid that Buster will have changed too much, so he reads up on all the places Buster had visited. His fears worsen when Buster doesn't call back or come over.
Art Garfunkel guest stars as a guitar playing moose who sings "The Ballad of Buster Baxter". Buster has returned to Elwood City. He's surprised by how much has changed and feels left out because of the things he didn't get to experience while he was away. Arthur decides to throw a party for him.
D.W. wants to prove to the Tibble Twins that she can read so she picks up one of Arthur's books and makes up a story because the twins can't read either. They are impressed as she rehashes events from the last two seasons into a sci-fi/fantasy adventure story about her.
Sue Ellen and the Brain are assigned to work on a project together (same assignment as "Arthur Goes Crosswire"). Francine and Buster say it will be easy as the Brain does almost all of the work by himself. Sue Ellen wants to help, but he doesn't let her. This turns into a struggle that nearly ruins their project.
Mr. Ratburn's class is asked to research their ancestors. Muffy and Francine try to one-up each other with who theirs were, even after each find nothing interesting. Even though Muffy is eventually caught lying about hers, Francine continues with her lie.
The Magic Toolbox is coming to Mr. Ratburn's class to put the kids on TV! The kids prepare for stardom, all practicing their various talents. The Brain is the only one not interested in appearing on the show, but when it turns out that the segment is not what the others expect it to be, they need his help.
Arthur and Buster are sorting potato chips and find a big green one. D.W. eats it so they trick her into think it's poisonous. Binky eats one, too, and they both make the best out the last days of their lives.
D.W. does not like to be reminded of the events in "The Chips are Down". Throughout the day, all of the kids and adults tease her about the green chip incident. She is furious that this went public, and blames Arthur but finds out it was her mom who told other people. She apologizes, but D.W. is upset again and runs off when her mom starts telling the story to someone else.
When graffiti stating "Binky Rules" mysteriously appears on the walls of the school, everyone thinks that Binky wrote it. Buster and Fern, who are well known for being good detectives, attempt to prove that he didn't do it. After more investigating, they realize that it was done by an unknown band called Binky to promote themselves. Värttinä guest stars as Binky.
Binky, the unknown band from "Binky Rules", has their first concert. Arthur gets to visit them backstage and struggles with whether or not he should bring his friends along and decides to do so at the last minute. They get to meet Binky backstage because Arthur's father is catering for them. When they meet them, they realize that they are actually holograms. Värttinä guest stars as Binky.
Arthur brings a cake his dad made to a party in his class celebrating Galileo's birthday. Everyone likes the cake so he asks his dad to make another one, but this makes him run behind on his other orders. He realizes this after the Brain's mom starts bringing ice cream to the school. A subplot has Mr. Ratburn attempting to get Mr. Read's cake by pretending to try to give anyone who is having one a schedule of Spring Reading, but his final attempt doesn't work when it turns out that Arthur and his dad aren't having cake; they're making ones for other people.
Francine accidentally takes her sister Catherine's backpack to school and discovers a magazine called "Popular Girl". Reading it convinces Sue Ellen and Fern to change their personality to become more likable.
Buster has never been mad at anyone for long, but he holds a grudge against Binky for telling the joke he was going to tell. This culminates to an onstage rant during a school talent show and Arthur has to set things right.
Mr. Ratburn's class is at a medieval fair competing for a trophy against a class from Glenbrook Academy led by Mr. Ratburn's former teacher, Mr. Pryce-Jones. During the competitions, Arthur is sidetracked by the sword in the stone and his classmates fear that Mr. Pryce-Jones may replace Mr. Ratburn if they lose.
The Tibble twins watch an episode of Terrific Turbo-Trooper Toy T-Bot Team and start dressing and acting like the T-Bots, a duo of crime-fighting robots (who bear a striking resemblance to the Power Rangers). They play roughly while pretending to fight crime and end up hurting D.W..
George becomes more popular with his ventriloquist dummy, Wally, and starts a short-lived ventriloquism fad at school. He starts acting less rationally as Wally starts falling apart, because before Wally, nobody noticed him.
Francine's family gets a new cat that Francine renames Nemo after her sister, Catherine, named him Rose Petal. Arthur is a dog person and doesn't like him, thinking he is trying to kill Pal. He dislikes him so much that it may end his friendship with Francine.
D.W. isn't as excited about her fifth birthday as her previous ones because according to Emily, after she turns five, she will no longer be a kid. Arthur goes over past events (from previous episodes) with her to cheer her up. This works and she goes on to her birthday party to make a wish.