"Apple Thief" is the eleventh episode in the third season of Adventure Time. It is the sixty-third episode overall.
Jake makes Korean food that Lady Rainicorn taught him to make for lunch, but Finn does not want to eat it because it smells weird. Finn suggests that they go to Tree Trunks' for apple pie, then chants "Apple pie, apple pie, apple pie" until Jake agrees. When Finn and Jake arrive at Tree Trunks' house, the house is in ruins, and Tree Trunks is on the floor, looking injured. Tree Trunks starts muttering, "Apples... my apples," and Jake says, "Apples?" then Tree Trunks lunges at Jake yelling, "You!" Finn pulls Tree Trunks off of Jake, saying, "Tree Trunks! It's us, Finn and Jake!" Tree Trunks comes to her senses, and tells Finn and Jake that someone stole her apples, and that without them, she cannot make apple pie. Finn and Jake yell, "Nooo!" and tell Tree Trunks that they will bring the thieves to justice.
So they go out to search for any clues about the thieves, soon finding a ditch where Raggedy Princess was trapped after she fell in. She says she was knocked out and had fallen there. When they think about where they could find any clue, Jake suggests that they go to the Candy Tavern, since it was there where he usually went after stealing purses (he justifies he did not know it was wrong). Going there looking for apples, they ask the barman if he knows anything about the crime they want to solve. Unfortunately, the barman thinks they are goody-goodies, so they rush to the bathroom where they dress like they were in a fight. Then, the barman guides them to some thieves, who suspect that they are all working for a rival gang. After a fight, Finn, Jake, and Tree Trunks escape and realize that when one of the thieves punched Finn, he left a big frown logo from his ring. Jake then leads them to a building with the logo, which he remembers from when he would steal bikes (he justifies he did not know it was wrong). The gang makes it inside, only to be trapped by the thieves. When a rival gang arrives, they challenge the thieves to a brawl, allowing Finn, Jake, and Tree Trunks to escape with a pig that was used by the first gang to eliminate (eat) rival gangs' members.
Upon returning to Tree Trunks' house, the pig says that he can "hear" apples in the house. Finn and Jake ask the pig if he is talking about "apples" (diamonds) or "apple-apples" (real apples), and the pig confirms they are apple-apples. The pig says that the apples are in the closet, but Tree Trunks denies it, saying that she is the only one who can open the closet. Tree Trunks opens it, causing a large amount of apples to spill out. Tree Trunks makes a phone call to the police saying that she has stolen her own apples. When a couple of Banana Guards arrive to arrest Tree Trunks, one of them says that her house could use a scarecrow, since there are a lot of crows gathering near the house. This causes Finn to think about everything that has happened and conclude that a family of magpies were the real thieves, since there are no footprints close to the apple trees, Raggedy Princess was knocked into a hole by something; and there is a nest of magpies on the top of Tree Trunks' house with a hole in the side where the apples that the mother magpie brought fell into the closet. Since Tree Trunks is innocent, Finn calls for a celebration and Tree Trunks says she will make an apple pie. She also invites the Banana Guards to eat with them, slapping one of the guards on the butt, and they all share a hearty laugh.
- When Finn, Jake, and Tree Trunks are being taken to the diamonds, one can see the head of a Gumball Guardian in the cellar.
- Inside the door of her closet Tree Trunks has a poster of a green humanoid muscled creature wielding a sword.
- There are several hidden messages written on walls in this episode:
- The wall in the bathroom reads "·- - wuz here," the first part being Morse code for "AT."
- Another message on the bathroom wall reads "A.T. 081012."
- When Finn, Jake and Tree Trunks were walking up to the secret hide out, there's another Morse code sign on the third building to the left that reads "·- - 4ever" with the first part meaning "AT."
- When Finn and Jake follow Wormo to the cellar, Jaybird puts his foot against the door to stop it from closing. Both he and Dr. J wear sneakers with the letter J on them, but Jaybird's sneakers are red.
- Finn showed up his hair with Jake and Tree Trunks while they're blending in.
- The pig in the cellar is a reference to the 2001 movie "Hannibal" when Mason Verger trains boars to eat human flesh to take revenge on Hannibal Lecter.
- Before the fight scene in the cellar, Dr. J and Jaybird yell "get 'em, boys!" which is, probably, a reference to a very similar scene from A Clockwork Orange movie. On the original scene, Billy Boy yells "let's get 'em, boys!" to his gang before fighting Alex Delarge's.
- The meal that Jake cooks (which Lady Rainicorn taught him) contains several Korean dishes. Recognizable dishes include:
- This is the first episode were Tree Trunks and Mr. Pig first met, the second time they appeared as they were in love with each other in "Dream of Love."
- In this episode it is revealed that Jake used to be a thug because he "did not know it was wrong; in "One Last Job" Jake's past crimes were explained further.
- The Candy People that are seen when Finn, Jake, and Tree Trunks enter the Candy Tavern disappear as they speak to the bartender and objects that were not there at first appear.
- Various objects and Jaybird's buds change places when Dr. J and the others show up. Also, the head of the Gumball Guardian disappears from the cellar when the candy thugs start to fight each other.
- Finn, Jake and Tree Trunks' dirtiness disappears as they were walking to the secret hide out.
- Even though that Finn said the apples in Tree Trunk's closet come from the magpies because there is a hole above the house, the apples still enter the closet even though there is no hole above the closet.
- It is never determined who were the ne'er-do-wells who knocked Raggedy Princess into the ditch.
- When Tree Trunks look into the mirror in the bathroom her hand on the left was brown but in the mirror her left hand was black.