Finn mysteriously receives a bag full of miniature versions of his friends and enemies and experiments with their lives.
The episode begins on a cliff by a lake at sunset. There, Finn and Jake are discussing relationships, with Finn wondering whether it is better to date someone with a similar or opposite personality. Jake tells Finn that love is not all about compatibility and science, but more about the "pumps-'n'-bumps" of one's heart. Finn then wonders whether the Ice King and BMO would make a good couple, which perplexes Jake.
As they talk, Magic Man spies on them and decides to prank them with his magic. Producing a small sack, he utters the incantation "Do what thou'st will be the whole piece of law," which apparently animates the bag's contents, followed by "I'm not coming back," which releases the contents of the sack from his power; he then tucks the sack into Finn's shorts.
While walking home Jake notices that Finn has something in his pants; misunderstanding him, Finn is embarrassed, before Jake points out the sack Magic Man left behind. Finn reaches inside and pulls out miniature versions of himself, Jake holding his viola, Princess Bubblegum, BMO, and Lumpy Space Princess. Jake worries that this is black magic, but his worry is assuaged by Finn, who points out that one of the toys is Jake playing his viola, while Lumpy Space Princess goes piggyback on him, Finn dances, and BMO struggles to right itself.
Excited, both Finn and Jake rush to their home, the Tree Fort, where Jake makes spaghetti with his special sauce and Finn continues playing with the Little People. He removes the characters he considers "C-list," which Jake considers impolite, especially since the characters left behind include the Ice King. At this, Finn remembers seeing a mini version of the Ice King's drums, and pulls it out for the Ice King to play. Mini-Jake joins in with his viola, much to Jake's chagrin, but then he notices that the two musicians have good chemistry.
Upon hearing the word "chemistry," Finn becomes quiet and thoughtful, ignores his food, and watches the various characters interact with one another: Lady Rainicorn and Princess Bubblegum talk to one another, Flame Princess and Lumpy Space Princess play a card game, Finn steals Lemongrab's camel while Lemongrab chases him, and Hunson Abadeer climbs onto a dinner plate, while Marceline glumly whizzes towards him (referencing the strained relationship the two have because of Hunson eating Marceline's fries), while Mr. Cupcake lifts dumb-bells in the corner.
That night, Finn cannot sleep, so he decides to play with the little people.
He starts to experiment with interactions of the little people starting with Mr. Cupcake and Lumpy Space Princess, who hit it off and begin to kiss. Finn is surprised by this and decides to experiment some more. He then removes Lumpy Space Princess and adds her to the magic sack and finds mini-Lady Rainicorn.
Peering out from his bedcovers at a sleeping Jake with mini-Lady Rainicorn in his hands, Finn looked apologetic for what he is about to do; when he adds mini-Rainicorn, the two of them ignore one another, with mini-Cupcake flexing his muscles, while mini-Rainicorn seems more content to chew on Finn's sleeping bag - however, Finn forces Lady into the arms of Mr. Cupcake, and they begin kissing.
Finn inserts mini-Jake, which prompts an argument in gibberish between the three and then Jake's and Lady's breakup. Finn then upturns the sack to release all the little people, and an intense look appears on his face. With all different characters, the possibilities would be endless.
The next morning, Jake finds Finn with a pile of books by Jay T. Doggzone, and asks Finn if he stayed up all night reading them; in fact, Finn had constructed a world for the little people to play in, and the book he appeared to be reading had a heartbroken Jake curled up inside it.
Jake wonders why his miniature looks so lonely and asks Finn to pass him mini-Lady, to which Finn replies that the two have broken up, and that Lady is pursuing a relationship with a "cool guy" - in fact, mini-Finn.
Jake becomes outraged when he sees Finn and Lady dating - Finn shows that he began relationships between a number of characters: mini-Marceline is shown repeatedly licking mini-Peppermint Butler, mini-Turtle Princess is shown spanking mini-Xergiok, referencing the real Xergiok's enjoyment of spanking the goblins over which he used to rule, and mini-Lollipop Girl is shown in a relationship with both Choose Goose and Abracadaniel.
Jake is confused and a little bit worried by Finn's actions and announces that he is leaving to stay with Lady Rainicorn until he can get over what Finn is doing.
After Jake leaves, Finn sees mini-Flame Princess and decides to see how the two figures interact with one another. Initially, mini-Finn is shy, while mini-Flame Princess appears bored, until Finn gives his miniature a piece of his cookie, and moves him closer to Flame Princess; he shares the cookie with her, and they begin to chew on it together in a way that looks like kissing (since the real Finn and Flame Princess cannot kiss) - Lady Rainicorn sees this and, heartbroken, begins to yell and weep melodramatically, before retreating into her book-house.
Finn adds in Princess Bubblegum in the middle and makes her give mini-Finn a backrub, and the two figures begin kissing; this makes mini-Flame Princess furious, and they begin to fight, during which Flame Princess sets Bubblegum on fire. Princess Bubblegum uses Lady Rainicorn's tears as a hose as an attempt to extinguish Flame Princess. Finn looked at the battle and turns a bit red as if a situation like that happened, Finn would have been the thing the Princesses were fighting for.
Sixteen weeks later Jake returns to see the fort a mess as Finn, still in the pajamas he was wearing 16 weeks ago, reveals that he has ruined the little peoples' lives, showing Mini-Xergiok in pain from mini-Turtle Princess spanking him too much, Choose Goose, Abracadaniel, and Lollipop Girl tangled up together, Mini-Marceline having eroded most of mini-Peppermint Butler from licking him, mini-Finn gazing into the distance atop a book (in mini-Finn's world, this book is the lakeside cliff where the episode began), Lady Rainicorn still weeping over her and Finn's breakup, and Princess Bubblegum with an exercise addiction following her breakup with Finn.
Despite Jake's pleas, Finn refuses to abandon them at this point since he has caused them so much trouble; however, he has no way to explain to the little people what he did. Finn attempts to contact Finn in various ways, including licking him (in the mini-world, this only manifests itself as large waves in the lake).
Jake suggests that they are on a different vibration level and that Finn should shake them. Finn shakes his miniature self at increasing speeds - when he gets to the correct speed, he appears as a face in the clouds, which puzzles mini-Finn. Jake notices mini-Finn's response and tells Finn to shake his miniature more slowly. He reappears in the clouds and explains that it was his fault that mini-Finn's life is ruined and that he will take care of it (at this point the clouds momentarily disperse, then reappear, because - much to mini-Finn's confusion - Finn's arm got tired from the shaking) and ends by saying "I'm not coming back," just as Magic Man said at the beginning.
He then moves on to Princess Bubblegum, Lady Rainicorn, and Flame Princess and explains the same information but says that they should make up and have a "dance party." Finn sets up music and the girls dance together, no longer mad at each other. He adds all the "C-listers" at Jake's instigation and create a huge dance party. All the miniatures dance, during which Jake notices that BMO and the Ice King are hitting it off - their miniatures are shown dancing together - thus answering the question of whether the two would make a good couple. At this point, the episode ends.
- Magic Man
- Little People
- Candy People
- Choose Goose
- Duke of Nuts
- Flame Princess
- Gary the Mermaid Queen
- Horse wearing shower cap
- Hunson Abadeer
- Ice King
- Lady Rainicorn
- Lumpy Space Princess
- Mr. Pig
- Mr. Turtle
- Rock Wall Thief
- Swamp Giant
- Turtle Princess
- Wizard Students
- Lady Rainicorn's colors on her body are only yellow, red, and green, instead of rainbow.
- Although the little Lady Rainicorn does not appear to be pregnant, Finn mentions that she is.
- Magic Man and Finn both said the same phrase in this episode. Magic Man says "I'm not coming back."
- This is the first time Flame Princess and Princess Bubblegum are shown interacting with each other, though they do so as toys.
- There is no Magic Man doll included in the bag, despite him being the one to create it (as seen in the title card of the episode)
- In one shot of Jay T. Dawgzone's book, one paragraph is repeated over and over: "Now to be clear, Jay T. Doggzone does not condone random flirtation with wanton babes, but rather careful consideration of which lovely honey gives your heart the bu-bumps. 'Cause it's all about the bu-bumps. Secondly, you got to remember to be smooth, no bodacious babe belongs with a bumbling baby beau bereft of bravado."
- Jake somewhat refers to this excerpt in the beginning of this episode that he should follow the lumps and bumps in his heart implying he read the Jay T. Dawgzone book.
- Miniature Finn is the only character apart from Lemongrab himself to ride Lemon Camel.
- Miniature Finn does not have socks as real Finn does.
- This is the final episode to premiere in 2012.
- The location where Finn and Jake are when they receive the bag is the same place where miniature Finn is spoken to by Finn at the end of the episode.
- The Wizard Students have no stars on their cloaks.
- When Little Finn is shown moping on the cliff, the title card music plays.
- The little people and their interactions are similar to the video game The Sims.
- Magic Man's incantation "Do what thoust will be the whole piece of law," is a reference to the phrase "Do what thou wilt shall be the whole of the Law." This was a key tenet of the religion Thelema developed by early 20th-century occultist Aleister Crowley.
- Finn's shaking of the little people in order to speak to them could be a reference to an idea formulated by some New Age thinkers about dimensions and vibrations. This idea states that those on earth exist in one vibrational dimension, and other beings exist on higher frequencies of consciousness (namely spiritual, god-like beings). Finn shaking the little people may be a play-off of individuals raising their vibrational frequencies to commune with spirits/gods (Finn manifests in a cloud to speak to them in the style that gods have been said to speak to mortals).
- The song Jake plays in the storyboard version is "Lonesome Fiddle Blues" (which is more widely known as the tune used in "The Devil Went Down to Georgia" by the Charlie Daniels Band). However, it was replaced with different music in the finished version of the episode.
- This episode could be a reference to the popular idea amongst fandoms, including the fandom of Adventure Time, of "shipping" which is the act of someone depicting two or more characters, whether through artwork or fictionalized text, being together in a romantic relationship.
- The open books on the table are written by Jay T. Doggzone, who was previously mentioned in the episodes "Reign of Gunters" and "I Remember You."
- In the book, Jay T. Doggzone is spelled differently from earlier appearances of the name, where it was Jay T. Dawgzone.
- In a previous episode, "Sons of Mars," Magic Man sings part of a song: "Memories drift in and out of my mind/ And the little people get left behind."
- The song Finn puts on at the end was reused from the music in the monster's belly in Belly of the Beast and is reused in "Breezy."
- Many characters from previous episodes (more specifically from season 1) appears as Little People. Some of these characters include: Donny, Tiffany, the Witch, some Marauders, and some Wizard Students.
- When the little Princess Bubblegum is carried out of the bag, she is not wearing shoes, but when she is standing up she is seen wearing shoes.
- After little Jake starts jamming with Ice King, Finn's sleeves went all the way down to his hands, similar to Fionna's sleeves.
- Near the end of the first scene where Finn and Jake are walking back to the house and they discover the sack full of little people, Finn's sword disappears.
- After putting little Finn, Jake, Princess Bubblegum, Lumpy Space Princess, and BMO, the outline of Finn's bear hat disappears and comes back on the next scene.
- Finn's hair makes another appearance, but after the scene in which Lady Rainicorn was crying, Finn's hair disappeared just like on "Who Would Win."
- Little Princess Bubblegum has ears even though the real Princess Bubblegum has no ears as seen in some episodes.
- Just before Finn starts shaking little Finn, little Finn's lower portion of his bookbag is yellow, as opposed to being lime green like it normally is.
- When Jake says, "Bring out the C-listers!" Marceline was with them, although she wasn't grouped with the C-listers the first time.
- The plate where little Hunson Abadeer is shown wasn't on the table, Jake only put two plates with spaghetti on the table.
- When Jake is saying, "Maybe we’re on different dimensional planes" the button on Little's Finn backpack is missing.
- When Jake came back little Finn was standing on a blue book after Finn said "I gotta fix this mess!" little Finn was standing on a different book. Also the books and a spool move.
- The picture of a chef behind the table later appears as only a grey background.
- When Finn takes little Flame Princess, he did not get burned by her; however when little Princess Bubblegum fights with little Flame Princess, her dress starts to burn. This may not be an error, as little Flame Princess's flames may only work on the little people.
- Lemongrab and his camel are missing from the dance party.
- Little Marceline is shown licking Peppermint Butler down to half his size as Jake says, "the destruction!", but when he joins the dance party at the end, he is fully intact.
- The title card was made by Andy Ristaino and Martin Ansolabehere.
- This is the last Adventure Time episode to air in 2012.
- This episode explores the manipulative-obsessive side of Finn's personality, he only concentrated on 'playing' with the little people and practically forgot about everything else for weeks until Jake came back. He seemed to enjoy creating conflicts and drama among them; as a hero, he needs things to fix and trouble in his life, otherwise, he feels uneasy when there is nothing to challenge him as seen in "Paper Pete."
- Jake was able to recognize Finn's behavior was not normal and unhealthy, but in "Card Wars" he wasn't able to acknowledge the way he was acting unlike Finn that in the end could realize he needed to stop and mend it.
- Finn's obsession with manipulating with other people's lives will come back to haunt him in "Frost & Fire," when his obsession in manipulating a fight between Ice King and Flame Princess forces her to leave him due to his uncaring behavior. A dream which foreshadows Finn's problems even has him speaking in the same language as the Little People in warning of what was to come.
This episode was censored in some countries. See Censorship of Adventure Time for more information.