- SpongeBob SquarePants
- Bubble Buddy
- Shiny Bubble (debut)
- Squidward Tentacles
- Ernest Borgnine (cameo) (storyboard only) 
- Eugene H. Krabs
- Gary the Snail
- Patrick Star (mentioned)
- Uncle Raymond (mentioned)
- Old Man Jenkins
- Nancy Suzy Fish
- Harold (red fish)
- Martha Smith
- Harold "Bill" Reginald
- Nat Peterson
- Frankie Billy
- Dennis (citizen)
- Nathiel Waters
- Construction worker (green)
- Unnamed Bikini Bottom Pillow Foundry worker (debut)
- Dinosaur bubble (debut)
- King Neptune (mentioned)
The episode begins with a bubble with a letter inside flying to SpongeBob's house while causing mischievous antics around town. It finally flies into SpongeBob's kitchen, who is enjoying a bowl of Kelpo cereal with Gary. SpongeBob opens the letter, which is from his old friend, Bubble Buddy, asking him to babysit his son, Shiny. Shiny appears out of the bubble holding the letter. SpongeBob introduces himself and takes Shiny to meet Squidward. Unfortunately, Shiny causes mayhem in Squidward's house and SpongeBob cannot find him. Shiny keeps flying in Squidward's house and destroying furniture. SpongeBob is being careful so Shiny will not pop from all the sharp objects in Squidward's house.Eventually, SpongeBob catches him and takes Shiny to the Krusty Krab. Then, he goes into Mr. Krabs' office and flies everywhere around him. Mr. Krabs is shiny and clean from the bubble soap and tells SpongeBob to let Shiny play in the dirty dishes. Then, while SpongeBob is cooking Krabby Patties, Shiny once again gets into mischief by sliding around and making the Krusty Krab floors slippery. All the customers keep slipping, so Mr. Krabs kicks them out. Then, Shiny flies into the city and gets into lots of trouble.
He goes into the Bikini Bottom Pin Factory, Bikini Bottom Scissor Works, and the Pitchfork Pantry. Then, SpongeBob decides to go to the Bikini Bottom Pillow Foundry since pillows are soft and harmless, only to find out that it is a dangerous place too due to the way pillows are produced.
When they get home, he feeds Shiny a hot dog in the form of a bubble, but then he pops. SpongeBob has the bubble soap to repair him. Finally, when he blows another Shiny, he grows two heads. Then, Bubble Buddy comes to his house to pick up Shiny. SpongeBob begins to apologize about Shiny, but Bubble Buddy says that it is okay, because sometimes it had happens to Shiny. Then, he traps Shiny into a bottle of bubble soap.
As they are leaving on a bubble plane, Shiny is normal again, blowing a raspberry out from the bottle and they go into the plane and fly away.
|( ‣ ) Associated production music|
|( • ) Original music|
|( ◦ ) SpongeBob music|
‣ Kalua Jubilee - Sage Guyton, Jeremy Wakefield [The opening.]
‣ Darting Around - Harry Bluestone [SpongeBob reads Bubble Buddy's letter.]
‣ Cocksure Capers - Phil Green [Shiny Bubble appears.]
‣ Tentically Speaking - Sage Guyton, Jeremy Wakefield ["I can't wait for all my friends to meet you."]
‣ Hawaiian Solo Steel - Jeremy Wakefield [Squidward's house is ruined.]
‣ Unknown Track 36 - Sage Guyton, Jeremy Wakefield [Shiny floats into a cupboard.]
• Hot Steel and Slide Licks (f) - Jeremy Wakefield ["No, guess not."]
‣ Tragic Bridge 4 - Phil Green ["There he is!"/Shiny floats near a broken lamp.]
‣ Hot Steel and Slide Licks - Jeremy Wakefield [Glass menagerie breaks.]
‣ Dramatic Bridge 4 - Phil Green [Shiny floats toward the ceiling fan.]
‣ Tragic Situation - Phil Green ["He's headed for that open window!"]
‣ Tipsy Turvy - Phil Green ["It looks like Shiny wants to be an artist."]
• Hot Steel and Slide Licks (t) - Jeremy Wakefield [Paint comes off.]
‣ Sailor's Sting 7 - Michael Bolger, Nicolas Carr [At the Krusty Krab.]
‣ Sponge Monger - Sage Guyton, Jeremy Wakefield [Customers slip on soap.]
‣ The Donut Dilemma - Nicolas Carr ["That's okay, Shiny."]
‣ Armed Attack - Jean Clero [Shiny disappears.]
‣ Bucaneers [#91] - Harry Bluestone, Emil Cadkin [Shiny floats toward the city.]
‣ Armed Attack - Jean Clero ["Shiny, where are you?"]
‣ Lap Steel - Nicolas Carr [SpongeBob is run over.]
• Hot Steel and Slide Licks (b) - Jeremy Wakefield ["That was a close one."]
‣ Grass Skirt Chase - Sage Guyton, Jeremy Wakefield [Shiny heads into pin factory.]
• Hot Steel and Slide Licks (o) - Jeremy Wakefield [SpongeBob deflates.]
‣ Crazy Mind - Harry Lubin [Shiny heads into Bikini Bottom Scissor Works.]
• Hot Steel and Slide Licks (a) - Jeremy Wakefield [SpongeBob falls apart.]
‣ Dramatic Impact 6 - Ivor Slaney [Shiny heads into the Bikini Bottom Pitchfork Pantry.]
‣ Drama Link (d) - Hubert Clifford ["Aaah, ow."]
‣ The Donut Dilemma - Nicolas Carr ["How many times do I gotta tell you?"]
‣ Rock-a-Bye Baby - ? [Shiny heads into the pillow foundry.]
‣ Working Machines - Gerhard Trede [Stock footage of steel foundry]
‣ Skipping to School - Sage Guyton, Jeremy Wakefield ["Here we are, home safe home."]
‣ Death and Destruction 1 - Harry Bluestone, Emil Cadkin [Shiny pops.]
‣ Hot Steel and Slide Licks - Jeremy Wakefield [Shiny grows a second head.]
‣ Marlin March - Sage Guyton, Jeremy Wakefield [The ending.]
As of December 12, 2017, The Internet Movie Database (IMDB) gives this episode a rating of 6.9/10 based on 108 ratings by users. TV.com users give this episode a rating of 7.9/10/10 based on 31 votes.
- This episode's title card is the same as the one for "Bubble Buddy," except that the word "Returns" is added to it and Bubble Buddy's name is squished up more.
- This is the first episode to have a title card reused outside of Mermaid Man and Barnacle Boy episodes.
- This is Bubble Buddy's second appearance in an episode after 11 years of not appearing.
- This was the final episode to premiere in 2011.
- In the letter from Bubble Buddy, it reads "We don't want him to go pop like his late Uncle Raymond." This is the first mention of any relatives of Bubble Buddy.
- Figuratively speaking, Shiny Bubble is SpongeBob's grandson because SpongeBob created Bubble Buddy and Shiny is Bubble Buddy's son. This could be implied that SpongeBob is Bubble Buddy's father.
- This is the first episode to use the track Unknown Track 36.
- Mr. Krabs references Bubble Buddy's original visit to the Krusty Krab in "Bubble Buddy," telling SpongeBob, "Bubble Buddy, eh? That guy still owes me money!"
- SpongeBob says one of the games that he and Shiny could play is the "Let's do nothing at all" game and claims that Patrick is really good at that one. It may be a reference to "Big Pink Loser" when Patrick wins a trophy for doing absolutely nothing longer than anyone else, which would make sense why he is good at the "Let's do nothing at all" game.
- As seen in other episodes, bubbles in the SpongeBob SquarePants universe have properties more similar to inflated balloons than bubbles. For example, when Shiny is caught in the blades of Squidward's fan, he does not pop. Instead, he spins around them, the way a helium-filled balloon would if caught in the same situation.
- Shiny shows no mouth signs of life until the end, just like his father in "Bubble Buddy."
- In "Bubble Buddy," the eponymous character drives an automobile home. In this episode, he rides an airplane home, implying he must have moved further away.
- This episode premiered five years after "That's No Lady" premiered, and seven years before "Goons on the Moon" premiered.
- This is the final episode of the series to contain the 2002 Paramount logo.
- In Germany, this episode has two title cards.
- This episode premiered on the same day as "Bubble Troubles," "The Way of the Sponge," and "The Krabby Patty That Ate Bikini Bottom."
- Xfinity/Comcast's description of this episode is actually for the original "Bubble Buddy."
- Squidward paints his self-portrait to resemble Napoleon Bonaparte.
- After SpongeBob reads the letter from Bubble Buddy, the spots on Gary's shell swap colors.
- This was a community error.
- When Shiny erases the mustache from Squidward's painting, no ink is seen on his torso. The mustache could not be erased without touching the nose.
- When SpongeBob and Shiny walk out of the pitchfork factory, SpongeBob has a pitchfork in his head. In the next scene, it is gone.
- When the dinosaur bubble appears, one of SpongeBob's sleeves is missing.
- Comcast/Xfinity says this episode first aired in April of 2008.
- Shiny floating into different sharp objects and factories, but doesn't pop while SpongeBob, who is trying to save him, ends up getting hurt.