|"What is that Thing?"|
|Number in season:||9A|
|Original Airdate:|| October 15, 1999|
January 27, 2000
|Written by:||Peter K. Hirsch|
|Storyboard by:||Jeremy O'Neill|
"Buster's Best Behavior"
A magical device helps everyone finish their seemingly impossible tasks — but what is it?
The plot begins with D.W. wanting to see a puppet show that Mr. Ratburn is holding at the library. Arthur doesn't want to go with D.W., but he reluctantly complies when their parents are too busy working to do so. Arthur decides it wouldn't be so bad if his friends went with him, so he goes to find Buster first.
However, Buster is trying to figure out an idea for the "Write An Episode For Bionic Bunny" contest, as the deadline is on that day. Arthur then goes to Francine's apartment, but Francine can't go either because she wants to be there for her cat, Nemo, because as of watching 20,000 Leagues Under the Sea, he has developed a fear of water so acute that even the sound of a shower being taken is enough to frighten him.
Muffy can't go because her new doll, Arnie, fell down a sewer, and she won't go without getting it out. Brain won't go without fixing his toy plane, which is missing a wheel. As Arthur walks home, disappointed, he finds a strange object. it's a metal spool with holes on the rim with red thread wound up around it. He ponders what it is unsuccessfully, when D.W. runs up and wants to see it. Arthur won't let her and they fight over it, causing it to fly from Arthur's hand and unintentionally catapult it to Brain. Brain doesn't know what it is, but it's about the right size for a wheel for his plane. He fits it on and flies it, and for a while it works but then falls off right next to Francine's apartment.
Francine spots it and has no idea what it is, but decides to try and use it to hypnotize Nemo into liking water. It works, and he promptly runs into Catherine's shower, now being attracted to water. Next, it rolls down the sidewalk to Muffy's sewer, where she spots it. Like the rest of them, she doesn't have a clue what it is, but uses the thread to hook it around Arnie's nose and pull her up. Then it rolls away from her and she chases after it. Francine sees, informs Muffy that it's hers, and joins the chase. Its next stop is Brain, who says he needs it for his plane to land. Then Arthur and Buster come up. Buster has no idea what's going on. The plane crashes, and Mr. Ratburn ends up with it. He informs the group that the thing is a bobbin, and he needs it for his puppet show. He then asks the kids to come, then they'll find out what the bobbin is. They all do so, and learn that the bobbin is actually an essential part to a sewing machine. Arthur is happy that his friends could come along. As they leave, Arthur tells Buster that he was the only one the bobbin didn't help. Buster says he wouldn't be so sure about that as he mails his contest entry into the mailbox. The scene cuts to a Bionic Bunny episode, where Bionic Bunny is fighting a bobbin with a huge nose attached, hypnotizing the cats of the city, controlled by its inventor, Elias Howe. It is revealed that the episode was written by Buster.
- Muffy uses the bobbin to save a plush anteater of hers named "Arnie." It wears Arthur's sweater - a clever in-joke.
- Nemo's design has changed in this episode after his debut in "Francine and the Feline," and has remained in subsequent seasons.
- In the prehistoric time flashback, while Arthur makes a fire with sticks, D.W. says "fire drill" like in "D.W. All Fired Up."
- In the beginning of this episode, D.W. says Mr. Ratburn's name correctly. But in "The Rat Who Came to Dinner," she frequently says his name incorrectly.
- Muffy's anteater doll Arnie resembles Arthur. “D.W. Tricks the Tooth Fairy” shows a monkey doll that resembles Francine.
- Brain's biplane crash-lands at the end of this episode, but it is seen again in "Nerves of Steal;" presumably, it was either repaired or replaced.
- Buster participates in an Idea for a Bionic Bunny Story contest. In 1998 there was a Create Your Own Arthur Episode contest. The winning entries became the plot of "The Contest".
- Francine mentions reading Twenty Thousand Leagues Under the Seas by Jules Verne and confirms that her cat is named after Captain Nemo.
- Elias Howe was a real-world inventor. He was the first to make a sewing machine with: a needle with the eye at the point, a shuttle operating beneath the cloth to form the lock stitch, and an automatic feed.
- Main article: What is that Thing?/Gallery