- Sheldon J. Plankton
- Karen Plankton
- Taylor Fishbowl
- Jennifer Millie
- Squidward Tentacles
- Mr. Stinky (debut)
- Frankie Billy
- Nat Peterson
- Cat (mentioned)
- Bee (debut)
- SpongeBob SquarePants
- Eugene H. Krabs
- HAZMAT Unit
- Fire Fish
- Don the Whale
- Harold "Bill" Reginald
- French Narrator
- Gary the Snail
- SpongeBob's Scallop (2 cameos)
- SpongeBob's Grandson (referenced as "grandchildren")
- Purple Doctorfish
At the Chum Bucket, Plankton is on a wagon preparing for another attempt to steal the Krabby Patty Secret Formula. He is pushed into the Krusty Krab and reveals from underneath the blanket covering the wagon a skunk (which he named Mr. Stinky) to everyone there. The customers think the skunk to be just a cat, but Plankton sets Stinky off by scaring him with a bee. All of the customers, Squidward, SpongeBob, and Mr. Krabs frantically leave the Krusty Krab due to the stink. Mr. Krabs knows that Plankton is in the Krusty Krab alone and takes one of SpongeBob's arms to use as a nose plug and heads inside. Mr. Krabs heads into his office to find Plankton surrounded the safe with dynamite. Unfortunately for Plankton, the safe has another safe inside and Mr. Krabs crushes Plankton with his fist and is tossed out of the window by SpongeBob. Mr. Stinky is removed from the restaurant by the HAZMAT Unit and sent away back up to the surface in a basket lifted up by balloons, only for the little number of balloons to bring him back down toward Bikini Bottom, causing the people to run away. Mr. Krabs, worried something like that will happen again, wants SpongeBob to take the secret formula home with him while he makes adjustments to his safe. However, the two of them didn't know Plankton was listening to everything with his severed antenna.
Later at closing time, SpongeBob tries to sneak home with the formula but is greeted by Plankton. The two of them talk for a little bit until SpongeBob excuses himself to go home. The next morning, SpongeBob is seen talking to Gary entrusting the safety of the secret formula to him. Plankton is spying on them and watches as SpongeBob leaves. Plankton then disguises himself as a door-to-door salesman selling snail products. However, Gary closes the door on him and Plankton angrily walks off. Moments later, Plankton is disguised as a Sweetie Patrol Girl and tries to sell cookies to Gary, but Gary ends up putting the sofa with Plankton on it outside. Plankton throws down the cookies in a fit of anger and gets blown up as a result, making a mental note that nitroglycerin is not a good substitute for vanilla extract.
Plankton finally manages to get inside SpongeBob's house by distracting Gary with a fake cut-out of himself. Plankton searches through SpongeBob's house tearing up everything in sight until he is confronted by Gary. Gary manages to beat up Plankton until Plankton escapes through Gary's shell thinking the secret formula is inside. Gary's eyeball starts to chase Plankton throughout his shell. SpongeBob eventually comes home and is horrified by the condition of his house. However, he is glad that the secret formula is safe (which was on top of his television the entire time). SpongeBob notices something is wrong with Gary and decides to take him to the vet. Back inside Gary's shell, Plankton makes it to the center of the shell and appears to have gotten the secret formula. However, it turns out that Plankton was hallucinating the entire time due to the fumes from Gary's shell and runs off into the sunset with what he believes to be the formula (which was actually SpongeBob's grocery list).
|( ‣ ) Associated production music|
|( • ) Original music|
|( ◦ ) SpongeBob music|
‣ Earl's Revenge - Sage Guyton, Jeremy Wakefield [Title card.]
‣ Stool Pigeon - Kenny Graham [Plankton going to the Krusty Krab.]
‣ Circus Parade (b) - Dick Walter [Skunk revealed.]
‣ Vibe Q Sting - Nicolas Carr [Customers crowd around the skunk.]
‣ Unknown Track 73 - "Gather in real close."
‣ Dramatic Cue (e) - Ronald Hanmer ["Time to trigger the stench!"]
‣ Sponge Monger - Sage Guyton, Jeremy Wakefield [The Krusty Krab is filled with skunk odor.]
‣ Alone in the Old House - Gregor Narholz [Krabs realizes Plankton is still inside the Krusty Krab.]
‣ Martial Tension - Sam Fonteyn [Krabs replaces his nose with SpongeBob's arm.]
‣ Battle at Sea - Johnny Pearson [Plankton blows up Krabs' safe.]
‣ Hot Steel and Slide Licks (l) - Jeremy Wakefield [Safe opens revealing another safe.]
‣ What Shall We Do with the Drunken Sailor - Okko Bekker [Krabs squishes Plankton.]
‣ Glory Road - Sam Fonteyn [The skunk is removed from the Krusty Krab.]
‣ Hot Steel and Slide Licks (e) - Jeremy Wakefield [Skunk floats into town.]
‣ Mission Improbable - Nicolas Carr, Barry Anthony [Krabs tells SpongeBob to hide the secret formula in his house.]
‣ Stool Pigeon - Kenny Graham [Oh, you're right, Professor Krabface."]
‣ Slinky Panther Pants - Nicolas Carr [SpongeBob talks to Plankton while he takes the formula to his house.]
‣ Evil Horror - Harry Lubin [Plankton spying Gary and SpongeBob.]
‣ Tomfoolery - David Snell [Plankton disguised as a salesman.]
‣ Domestic Fun (a) - Ernest Tomlinson [Plankton appears disguised as a girl scout.]
‣ Domestic Fun (c) - Ernest Tomlinson [Gary slams the door.]
‣ Hot Steel and Slide Licks IV - Jeremy Wakefield [Plankton dazed.]
‣ Cartoon Sting 7 - Plankton enters SpongeBob's house.
‣ The Fruitcake Vendor - Nicolas Carr, Barry Anthony [Plankton tears the house apart looking for the formula.]
‣ Cartoon Sting 5 - Plankton goes up to SpongeBob's bedroom.
‣ Harp Ding - Nicolas Carr [Gary gets an idea.]
‣ Cartoon Sting 2 - Plankton exits SpongeBob's bedroom.
‣ Unknown Track 3 - Sage Guyton, Jeremy Wakefield [Plankton falls into Gary's traps.]
‣ Armed Attack - Jean Clero [Gary hits Plankton.]
‣ Magic Potion 1 [#95] - Harry Bluestone, Emil Cadkin ["Of course! What a fool I've been!"]
‣ Misty Menace - Max Saunders [Plankton enters Gary's shell.]
‣ Tower of Evil - Magnum Opus [Gary's eye chases Plankton.]
‣ Dramatic Bridge 1 - Phil Green [SpongeBob sees his house destroyed/]
‣ Misty Menace - Max Saunders [SpongeBob worries about Gary.]
‣ Parallel Dimension - Gregor Narholz [Plankton running through Gary's shell.]
‣ Evil Horror - Harry Lubin [Plankton falls into the center of the shell.]
‣ Vibe Q Sting - Nicolas Carr ["What's that?"]
‣ Unknown Track 21 - "This is it! Just like I thought!"
‣ The Oracle - David Farnon [Choir.]
‣ Parting of the Clouds - Nicolas Carr ["Let me bask in its glory!"]
‣ Twelfth Street Rag - Sage Guyton, Jeremy Wakefield [Ending.]
- As of July 23, 2017, The Internet Movie Database (IMDB) gives this episode a rating of 8.5/10 based on 30 ratings by users. TV.com users give this episode a rating of 8.2/10 based on 5 votes.
- The title card for this episode is similar to "Big Sister Sam."
- This episode marks the first use of the "Tomfoolery" track since the Season 7 episode "Karate Star," and the first use of the "What Shall We Do with the Drunken Sailor?" track since the Season 6 episode "No Nose Knows."
- This is the first time a main character says "MY LEG," Plankton used it after Gary slammed the door on him.
- This is the second time Plankton sells cookies in an attempt to get the secret formula. The first time was in "Sweet and Sour Squid."
- This is the second time SpongeBob lies about his hair. The first time was in "The Smoking Peanut."
- This is the third time the word "Pineapple" is in the title of the episode. The first was in "Home Sweet Pineapple," and the second was in "Pineapple Fever."
- This is the first time that the word "Pineapple" is in the title, but not using the same background as the others.
- This is the third time Plankton uses the phrase, "I went to college!" against someone. The first time was in "Plankton!," and the second time was in "Imitation Krabs."
- List of objects seen in Gary's shell when Plankton goes inside:
- A bowling ball
- A toothbrush
- A clarinet
- A nickel
- A teddy bear (possibly Beary)
- A treasure chest
- A diamond
- This episode reveals that Plankton hates pineapple.
- This episode reveals that shortly after SpongeBob made his first Krabby Patty, which was featured in "Friend or Foe," he got it bronzed.
- In this episode, the Chum Bucket hand can open. However, in "20,000 Patties Under the Sea," the hand transforms into a submarine.
- Plankton may have replaced it since it crashed in that episode.
- This episode premiered seven years after Square Roots: The Story of SpongeBob SquarePants premiered on VH1 and the re-release of SpongeBob's Greatest Hits, and on the title character's 30th birthday.
- This episode premiered in Canada on October 14, 2016, which was exactly three months after it premiered in the United States.
- This episode might take place shortly after "Help Wanted" as SpongeBob has the Krusty Krab poster, which only ever appeared in that episode.
- However, it is possible that SpongeBob put it back up to lead Plankton off the trail of where the formula was.
- Coincidentally, both this episode and the sister episode end with Plankton at sunset.
- This episode is one of the few episodes to feature a land creature besides Sandy. In this episode a skunk is shown.
- This episode takes place after "Sweet and Sour Squid" because in that episode, Plankton disguised himself as a Sweetie Patrol Girl and used his regular voice. In this one, he realized to change his voice (probably remembering the time he tried to fool Squidward).
- Plankton is disguised as a Sweetie Patrol Girl and tries to sell Sweetie Patrol Cookies. This is a reference to the Girl Scouts and Girl Scout Cookies.
- The title is a spoof of "Home Invasion."
- Mr. Krabs saying "Why you little" to Plankton as Plankton tries to blow up the safe is a reference to The Simpsons.
- Gary made a Rube Goldberg machine, when trying to catch Plankton. These machines were made in an episode of the 1999 series Zoom.
- The Greek title for the episode, "Ψάξε, ψάξε, δεν θα την βρεις" (Look for it, look for it, you won't find it) is a reference to the phrase, as well as the Greek traditional song "Το Δαχτυλίδι" (The Ring).
- Some of the characters are not drawn with noses, yet they are able to smell the skunk spray.
- Plankton can't smell, but tells Gary that he should really use the slime deodorant.
- The safe shows the numbers 15-30-75, when it's supposed to be 15-30-45.