- Eugene H. Krabs
- Sheldon J. Plankton
- SpongeBob SquarePants
- Karen Plankton
- Bikini Bottom Prison Guard
- Sheldon (fish) (green)
- Purple cellmate (debut)
- Reggie (debut)
- Dennis Rechid
- Squid Cellmate (debut)
- Nancy Suzy Fish
- Light blue cellmate (debut)
- Norma Rechid
- Incidental 47
- Martha Smith
- Abigail Marge
- Evelyn Annette
- Debbie Rechid
- Whale cellmate (debut)
- Cashier (orange) (debut)
- Squidward Tentacles (as the purple cellmate's disguise)
- Sheldon (not green)
- Phil (yellow)
- Medley Fishbowl
- Billy Fishbowl
- Jennifer Millie
- Incidental 2
- Frank Fishbowl
- Harold Bill Reginald Scott
- Officer John Slugfish
- Officer Rob Johnson
- Ray Buffer
The episode begins with the narrator explaining the Bikini Bottom Jail, mainly its newest member, Plankton. The warden lets all of the prisoners out, including Plankton. The latter hears SpongeBob calling out to him. Plankton wants to know what is SpongeBob doing there, as SpongeBob says that Mr. Krabs arranged for him to work at the jail on weekends and told him to watch over Plankton. Plankton does not like the idea, but the prison warden tells him to quiet down.
The scene changes over to a room where Karen is about to send over a cake to SpongeBob, which is for Plankton. Plankton asks if Karen had put the file in the cake, but Karen just laughs, for she thought he was joking. Plankton unsuccessfully tries to jump over the glass, but SpongeBob grabs him.
In the cafeteria, Plankton attempts to eat his food, but a purple cellmate grabs some of his beans and eats them. Another green cellmate drinks Plankton's milk and then Plankton gets eaten by a light blue cellmate. Plankton yells out that he is the evilest genius and yells out his name. The purple cellmate, thinking the light blue cellmate is talking, does not believe him, saying he and the others are fans of Plankton. Plankton calls out his name again and then the purple cellmate punches the light blue cellmate in the stomach, which causes Plankton to be punched out and crash into the wall. The purple and green cellmates start to beat up the light blue cellmate until Plankton breaks it up. Plankton introduces himself to the cellmates and they say how they are going to do everything that Plankton says. Plankton gets excited saying how easily he could get the Krabby Patty secret formula.
Outside, Plankton is explaining to his cellmates how to escape from the Bikini Bottom Jail. The cellmates have ideas but Plankton tells them they need better ones. The whale cellmate says they could break out only if they had chum and the other cellmates agree, explaining how they used it in crimes before they got busted. Plankton is surprised by the cellmates saying how chum is great for committing crimes. Plankton asks if chum is great for eating but the cellmates do not think so. Realizing he overlooked the capabilities of chum, Plankton then agrees to make chum for the cellmates, and they all cheer. Inside Plankton's jail cell, Plankton, and his cellmates are creating chum using different kinds of items. SpongeBob overhears them and runs to the Krusty Krab to warn Mr. Krabs. At the Krusty Krab, SpongeBob tells Mr. Krabs that Plankton is planning to break into the Krusty Krab with his cellmates. Mr. Krabs insures SpongeBob that he will handle the problem.
Back at Bikini Bottom Jail, a Prison Warden is talking to two of Plankton's cellmates saying why they are out of their cells. The purple cellmate says that the green cellmate said the napkin smells like kelp berries. The prison warden smells the napkin and falls down, unconscious. The Purple and Green cellmates bring the Prison Warden inside while Plankton arms himself with chum and a bomb. The Whale cellmate then launches Plankton to the other side of the prison and Plankton plants the bomb on the wall. Plankton gets spotted but the bomb goes off and blows a giant hole in the wall. However, the Prison Wardens then start filling up the wall, making it impossible for Plankton to get, though. However, they get stuck and Plankton uses the opportunity to lead all of his cellmates out through the front door. At the Krusty Krab, SpongeBob notices Plankton and all of his cellmates preparing to invade the Krusty Krab. Mr. Krabs says that they are ready for them while Plankton yells out to his cellmates to bring him the formula. Plankton's cellmates begin breaking down the door using the whale cellmate as a battering ram and they successfully break-in. The Whale Prisoner then opens the safe with Mr. Krabs urging Plankton not to get it but Plankton does not listen. As Plankton heads toward the "formula," the curtain rises and the entire Bikini Bottom Police Force emerges from it. Mr. Krabs revealed that he knew of Plankton's attempted break-in and had enough time to hide the entire Police Force in his safe. The Police Force then takes Plankton and the rest of his cellmates back to jail. SpongeBob congratulates Mr. Krabs on how he always wins, but then the entire Krusty Krab falls apart. The episode ends when Mr. Krabs replies "Yep, I'm a winner."
- Plankton getting poked by a training baton.
|( ‣ ) Associated production music|
|( • ) Original music|
|( ◦ ) SpongeBob music|
• Greenhorn Rag - Nicolas Carr, Sage Guyton, Jeremy Wakefield [Title card]
‣ Hercule Poirot - Gerhard Trede [opening]
‣ Seaweed - Steve Belfer [SpongeBob as a prison guard]
‣ An Underwater Conversation - Barry Anthony [Karen brings Plankton a cake]
‣ ? ["You mean love?"]
‣ An Underwater Conversation - Barry Anthony ["What?! The file?"]
‣ A Casual Conversation - Nicolas Carr, Barry Anthony [Plankton at lunch]
• Tension Bits - Nicolas Carr, Sage Guyton, and Jeremy Wakefield ["Hey! What did you say?"]
‣ Sponge Shredder - Nicolas Carr, Fabian Fernandez ["We're all big fans of that maniacal little miscreant!"/Prisoner is punched in the stomach, ejecting Plankton]
‣ Hot Steel and Slide Licks - Jeremy Wakefield [Plankton falls on the floor]
‣ Bubble Poppin' Boys - Nicolas Carr, Barry Anthony ["Gather round, fellow convicts!"]
‣ Noodly Shenanigans - Nicolas Carr, Barry Anthony ["Okay, gang."]
‣ Dramatic Cue (e) - Ronald Hanmer [guy smears chum on his face]
‣ Dramatic Bridge 4 - Phil Green ["What a hideous monster!"]
‣ Noodly Shenanigans - Nicolas Carr, Barry Anthony ["Have you ever tried eating it?"]
‣ Call the Cops! - Gary James Crockett, Jay Stuart Glover [chum bank robbery]
‣ Bubble Poppin' Boys - Nicolas Carr, Barry Anthony ["If it's chum you want, it's chum you shall have!"]
‣ Unknown Track 29 - prisoners making chum
‣ Parting of the Clouds - Nicolas Carr [choir]
‣ Murder in Mind - Kenny Graham [SpongeBob hears about the jailbreak]
‣ The Tip Top Polka/The Cliff Polka - Chelmsford Folk Band [Krabs paints a picture of a dollar]
‣ Long Distance Mission [#17] - Phil Green [SpongeBob tells Krabs about the jailbreak]
‣ Victim 5 - Harry Lubin ["Whoa there!"]
‣ Long Distance Mission [#20] - Phil Green [prison guard passes out]
‣ Hercule Poirot - Gerhard Trede [detonator made out of soap]
• Hot Steel and Slide Licks (b) - Jeremy Wakefield [prison wall blown up]
‣ Pell-Mell - Sam Spence [prison guards blocking the gap in the wall]
• Hot Steel and Slide Licks (t) - Jeremy Wakefield [prison guards struggling to move]
‣ Winds of War [#8] - Harry Bluestone, Emil Cadkin [prisoners escape through the front door]
‣ Cloak and Dagger [#70] - Phil Green ["Yes!"]
• Hot Steel and Slide Licks (n) - Jeremy Wakefield [" Sorry, boss."]
‣ Unknown Track 57 - Plankton approaches the safe
‣ Bikini Bottom Police - Nicolas Carr [cops]
• Tentically Speaking - Sage Guyton, Jeremy Wakefield [ending]
- This is available on the SpongeBob SquarePants Vol. 15, Bizarro Bikini Bottom, It Came from Goo Lagoon, Bikini Bottom's Most Wanted, Evil Spatula, Complete Ninth Season, Next 100 Episodes, and The Best 200 Episodes Ever DVDs.
- Both this episode and its sister are Plankton-related.
- This episode marks the first time that an animated sperm whale has been seen that was not Pearl.
- This is the fifth time Plankton goes to jail. The first was in The SpongeBob SquarePants Movie, the second was in "Krabby Road," the third was in "Sweet and Sour Squid," and the fourth was in "Fiasco!"
- It's unknown why Plankton was in jail but at the end he was arrested for breaking out of jail along with the other imamates.
- One of Plankton's cellmates is a whale that looks similar to Pearl.
- Plankton isn’t afraid of the whale in this episode, but he was afraid of Pearl in "One Coarse Meal."
- The recipe for chum in this episode is different than that revealed in the episode "Spongicus."
- Chum is actually the guts and organs of fish, yet this was not used in the recipe.
- It’s revealed that chum is used to committing crimes throughout Bikini Bottom.
- This is one of few episodes where SpongeBob calls Plankton by his first name, "Sheldon."
- Although Squidward doesn’t appear in this episode, a prisoner uses chum and looks and laughs like him.
- Even though Karen points out the silliness of having a nail file in a cake, one of the prisoners is seen with a nail file and a cake in his stomach when he eats Plankton.
- This is the seventh episode in which, at no point, SpongeBob wears his normal clothes. The first is "Ripped Pants," the second is "Walking Small," the third is "The Fry Cook Games," the fourth is "SpongeGuard on Duty" (not counting the live-action SpongeBob costume), the fifth is "Mermaid Man vs. SpongeBob," and the sixth is "The Inmates of Summer."
- The original German title of this episode, "Fraß macht frei" (Chum Sets You Free), was canceled 10 days before its premiere on Nickelodeon Germany, due to the reference to the German phrase "Arbeit macht frei," known for appearing on the entrance of Auschwitz and other labor camps. However, the episode premiered with the title unchanged, which resulted in the episode being banned. On August 1, 2015 (approximately four months after the German premiere), the episode finally reran with a new title, "Knastbrüder", which means "Jailbird".
- As a result, in Germany, this episode has two title cards.
- The German version of Bikini Bottom's Most Wanted DVD still calls the episode "Fraß macht frei and Knastbuder".
- Plankton's prisoner number is #655321, which is a reference to the character Alex in the book/film A Clockwork Orange, who shares the same number.
- Earlier in the episode, when Dennis emerges from his cell, he is tall. After he and some other prisoners help break into the Krusty Krab, Dennis is much shorter.
- Plankton mentions that the people of Bikini Bottom are to be free from cruel and unusual punishment ("Excuse me, doesn't this count as cruel and unusual punishment?"). However, it has been shown that characters had been subjected to it in the past such as Squidward ("Little Yellow Book") and Patrick ("The Smoking Peanut").
- When the whale cellmate turns around and looks at the safe in the Krusty Krab, SpongeBob's pant leg color is white instead of brown.