Chowder and the gang must make a special delivery to a food suit-themed party hosted by Mr. Fugu.  However, the dish (containing "shrinky pinky" spice) spills over Chowder, Mung, Shnitzel, and Truffles and shrinks their fruit costumes, leaving them stuck in the city in only their underwear.  They must try and find new costumes before making it to the party.

Trivia

• Panini has a non-speaking cameo appearance.
• This episode appeared On Demand and on iTunes before its original air date on Cartoon Network.
• This episode aired on December 10, 2009, one hour before Round 2 of Total Drama's Red Carpet Rivalry.
• Craig McCracken helped write this episode.
• At the beginning, in order to save the fruit suits, Mung broke the fourth wall by saying this phrase: "Scene 14! Scene 14! Retake, retake! Please remove flaming cauldron and replace with pillows provided! Thank you!"
• This is one of the episodes where Endive is shown as a giant, but only for a brief second.
• This is Mung's third time in his underwear. The other times were: "The Hot Date" and "The B.L.T's". This is Shnitzel's fourth time. His first two times were "The Wrong Customer" and "The Thousand Pound Cake". His third time was "The Garage Sale".
• This was the last episode to premiere in 2009.
• When Gazpacho gives the gang his pants, he also took off his shirt and shoes, but did not give them to them. He could've put the shirt and shoes in one of the barrels, but he was still wondering to do with them after he gave them his pants.
• When the gang was chased by the police and the mob, this a reference to the classic Beatles movie, Help! Craig McCracken (the writer of this episode) is a huge Beatles fan.
• The name of the episode is named after the phrase 'birthday suit', which means no clothes. An example that supports this is that they technically did not have any clothes until they received the new fruit suits. But the real reason they called it this is that the suits were actually birthday suits as in suits for a birthday party. (However, Mr. Fugu's party wasn't for his birthday.)
• Chowder's costume shrank, but his hat and pants didn't shrink. (This is probably because they weren't hit by the dish.)
• When it shows the iron fist party, Mung has an iron fist. But when Chowder punches Mung in the face, Mung has no iron fist.
• The storyboard for this episode was finished in March 3, 2009.

Fun Facts

• The Fruit Suit vendor enjoys show tunes. The vendor also has an Indian similar to Apu Nahasapeemapetilon from The Simpsons.
• Chowder and Sergeant Hoagie both sing the same show tune: "I am a pretty butterfly; I bring the pretty to your eye."

Quotes

Chowder: The suits, the suits, it's all about the suits, and if you eat too many beans, you'll get the toots!

Chowder: [British Accent] Oh I do love a good party! Will there be heaps of dancing and delightful, frivolous diversions?

Mr. Fugu: I never knew I could have an underpants party! This is SOOOO much better than a fruit party!

Mung: (to Endive) Oh, yes, you will see me at the party. You will see me!

Gallery

v • e List of episodes
Season 1	The Froggy Apple Crumple Thumpkin • Chowder's Girlfriend • Burple Nurples • Shnitzel Makes a Deposit • Grubble Gum • The Cinnamini Monster • Certifrycation Class • The Sing Beans • The Wrong Address • The Wrong Customer • Mahjongg Night • Stinky Love • The Thrice Cream Man • The Flibber Flabber Diet • Gazpacho Stands Up • A Taste of Marzipan • The Puckerberry Overlords • The Elemelons • At Your Service • Chowder and Mr. Fugu • The Vacation • The Sleep Eater • Sniffleball • Mung on the Rocks • The Heavy Sleeper • The Moldy Touch • The Bruised Bluenana • Shnitzel and the Lead Farfel • The Thousand Pound Cake • The Rat Sandwich • Chowder Loses His Hat • Brain Grub • Shnitzel Quits • The Broken Part • The Meach Harvest • Banned from the Stand • Créme Puff Hands • The Apprentice Games
Season 2	The Arborians • The Garage Sale • Panini for President • Chowder's Babysitter • The Fire Breather • The Flying Flinger Lingons • Hey, Hey It's Knishmas! • Chowder's Catering Company • The Catch Phrase • The Hot Date • Shopping Spree • The Party Cruise • Won Ton Bombs • The Big Hat Biddies • The Deadly Maze • Kid Shnitzel • Gazpacho Fights Back • The BLT's • The Trouble with Truffles • The Dinner Theater • Big Ball • The Brain Freeze • The Snail Car • The Lollistops • Endive's Dirty Secret • Big Food • Paint the Town • The Blackout • The Dice Cycle • The Chain Recipe • The Garden • Sheboodles • Gazpacho Moves In • My Big Fat Stinky Wedding • Apprentice Appreciation Day • The Grape Worm • A Faire to Remember • Tofu Town Showdown
Season 3	Hands on a Big Mixer • The Blast Raz • The Spookiest House in Marzipan • The Poultry Geist • The Apprentice Scouts • The Belgian Waffle Slobber-Barker • A Little Bit of Pizzazz! • The Birthday Suits • The Heist • The Prank • Old Man Thyme • Chowder's Magazine • Weekend at Shnitzel's • Taste Buds • Gazpacho! • The Toots • Chowder Grows Up