"Bonnibel Bubblegum" is the fourth episode in the ninth season of Adventure Time. It is the two hundred and seventieth episode overall.
The episode begins with Finn, Jake, Princess Bubblegum, and Marceline, relaxing and swimming at an apple cider pond. Finn brings Princess Bubblegum a cup full of cider. This cup was previously given to BMO by a mysterious scientist in "Always BMO Closing." PB acknowledges that it reminds her of a cup her Uncle Gumbald once had. Finn then asked the princess to tell them about her family. Though reluctant, Bonnibel decides to tell them. The scene cuts to a flashback, around 800 years before. Bonnibel was lonely, wandering the post-apocalyptic wasteland, scavenging. She then went to her home, where she resided with her brother, Neddy. She told Neddy that she wanted to make them family, as they only had each other, and nobody else. PB then brought in large pieces of gum and set up a device that gave them life. The first relative was an elder female, named Aunt Lolly, the next was a tall young male, known as Cousin Chicle, and the last was older male known as Uncle Gumbald. The family lived a simple happy life together until Gumbald started getting some ideas of his own. He chopped down the taffy trees they had planted and decided to use them to build a cabin then revealed his plans to build a candy city. However, Bubblegum decides to stop his plans and adds a butterscotch lake where Gumbald was going to build his city. Gumbald then became upset with Bonnie and grows treacherous to her so he starts to hatch a plan. He, Chicle and Lolly create Mr. Cream Puff to serve as Bubblegum's boyfriend and to keep her busy while they plot to overthrow her.
When Bonnibel gets back, she overhears her relatives insulting her and planning to poison her with a chemical to make her dumb like Mr. Cream Puff. Gumbald then poisons Chicle and Lolly turning them into the simple-minded candy people. Lolly becomes a talking pinata known as Manfried. While Chicle becomes a brown candy ball known as Crunchy. Bubblegum then confronts her Uncle, who voices that he is her equal but she states he is evil as he plans to turn her into a docile candy person and "take care of" her brother Neddy. Angered, Bonnibel used her pea shooting Taser to spill the poison on him turning Gumbald. Splashed with the poison, Gumbald transformed into the talking bowl of fruit punch known as Punchy. With her family turned into harmless, silly candy people, Bonnie first found the situation difficult. However, she soon noticed that her relatives seemed happier in their new forms. Prubs then chose to keep her family as their new candy forms and have them as her companions. Finally succumbing to the little name her Uncle called her, she chose to have her new citizens call her princess.
The scene then cuts to the present, in which the group is now in the Tree Fort. Washing the cup, PB is reminded once more of her family when she sees that it is one of the monogrammed cups Gumbald had made 800 years ago. Shocked, she asked BMO where he got the cup. BMO then said that the man on the cup (Gumbald) gave it to him, revealing that he is somehow back.
- Princess Bubblegum
- Great Uncle Gumbald/Punchy (flashback)
- Aunt Lolly/Manfried (flashback)
- Cousin Chicle/Crunchy (flashback)
- Neddy (flashback)
- Mr. Cream Puff (flashback)
- Science (cameo, flashback)
- Strangely, two of the three first candy people are not actually candy, as a piñata and a glass bowl of fruit punch is not considered candy.
- Bonnie riding over the desert hills on an ox in post-apocalyptic gear bears a striking resemblance to the opening of the movie Tank Girl. The horn-like bumps on Bonnie's helmet are similar to the ones on Tank Girl's and both oxen are wearing pink and green goggles.
- In the beginning of the flashback, when young Bonnibel is riding through the wasteland on a yak/bull, it is similar to the first scene with Rey in Star Wars: The Force Awakens, when she is scavenging through Jakku.
- The silver goblet from "Always BMO Closing" reappears.
- The taffy tree field (which had previously been seen as a field of stumps in "Susan Strong" and "Reboot") is shown being cut down by Gumbald.
- The cabin that PB lived in from "Hot Diggity Doom" to "The Dark Cloud" also makes an appearance, along with Lake Butterscotch, whereupon their origins are revealed.
- Although Princess Bubblegum had mentioned in "Hot Diggity Doom" that the cabin was built by Gumbald, she did not reveal the full circumstances and impact of its creation until now.
- Mr. Cream Puff was previously mentioned and shown to be PB's "boyfriend" in "Slumber Party Panic" and "The Vault."
- After being mentioned several times, Gumbald is finally introduced.
- When Princess Bubblegum says "families are tricky," Finn and Marceline both nod in relation (Finn in reference to his relationship with his biological parents and Marceline in reference to Hunson Abadeer). Jake doesn't relate, though unknowingly he has a complicated family background as well.
- Banana Guard 16's tale about Bubblegum from "The Thin Yellow Line" is proven to be exaggerated, but correct. He mentioned that "when the first candy people rose against her, she transformed them into hideous monsters." In reality, she transformed them into more simple-minded candy people.
- It's possible this is the reason Princess Bubblegum made the present candy people dumb - so what happened with Gumbald and the others won't happen again.
- The taffy tree field that Gumbald cuts down in the night is right in front of the early Candy Kingdom, while in its appearances in the present, the field is significantly farther away from the kingdom (at the entrance to the Hyoomen's hideout) than in the flashback.
- It is possible, however, that Bonnie is simply remembering parts of the story incorrectly, as its also quite improbable that the 10 or so taffy trees Gumbald cut down were enough to build the entire cabin.