SpongeBob receives a note from his cousin BlackJack, saying that he has been released from prison and is going to pay SpongeBob's parents a "visit." When he arrives at their house, it is wrapped with police tape, and all of the furniture is covered in plastic, which leads SpongeBob to believe a crime was committed at his parents house. He finds another note from BlackJack, this time saying he's going to pay SpongeBob's Grandma a visit. SpongeBob arrives at Grandma SquarePants' house, and she says BlackJack recently called her, and left a message for SpongeBob, saying he has some "loose ends to tie up." This results in SpongeBob thinking BlackJack tied up his parents
SpongeBob seeks help from his uncle, Captain Blue SquarePants, a retired police captain. Instead of helping SpongeBob save his parents from BlackJack, he makes SpongeBob partake in manual labor, including lawn mowing, building a fence, trimming a coral tree and much more. When SpongeBob finishes, Captain Blue drives him to BlackJack's house. SpongeBob stands in front of BlackJack's front door for a moment regretting his decision, when he hears mother scream from inside the house. SpongeBob instantly runs into BlackJack's house, and into the basement. SpongeBob goes in to confront his foe and save his parents, but it is revealed that his parents were never in any danger, and that they are holding a party for BlackJack to
celebrate his release. They explain to SpongeBob that BlackJack has renounced his "criminal" ways of littering, and that their house was closed off due to a krill infestation. BlackJack then enters the room, still intent on beating up SpongeBob, but SpongeBob is now prepared to stand up for himself. As BlackJack charges at SpongeBob, it is revealed that BlackJack is no bigger than SpongeBob's foot, and that he cannot do any harm whatsoever.
The return address that has been covered by saliva can be made out as "BlackJack, 133 Coral Rd or Bd, Bikini Bottom."
In this episode, SpongeBob's house is just referred to as "The Pineapple, Bikini Bottom," instead of 124 Conch St.
This is the third episode to have a title card that only has light around the text. The first and second were "Squirrel Jokes" and "Funny Pants" respectively.
When SpongeBob flashes back to when he was a kid, he is shown wearing a bow tie.File:Bowl.png"BlackJack" (left) and "Grandma's Kisses" (right)
Somewhere in Mid-2009, Nickelodeon airings of this episode were updated to use "Secret Agent SquarePants" as title card music instead of K-55, possibly due to rights issues. Nicktoons airings still have the old title card music as of June 2018.
The bowl on Grandma's counter is the same as the one in "Grandma's Kisses" but with a different, more clearer shape.
This is the second appearance of SpongeBob's grandmother, who first appeared in "Grandma's Kisses.
In "Home Sweet Pineapple," SpongeBob says "goodbye Bikini Bottom" implying that his parents do not live in Bikini Bottom, yet in this episode, their house is in Bikini Bottom.
When SpongeBob is at his parents' house, there is an image above the couch, that shows a sun on some rocks in goo. In SpongeBob's idea of what happened, the image shows dark rocks, like it is night.
Unless the clock at SpongeBob's parents' house is really broken, the time goes from 2:00 when SpongeBob arrives to 9:00 when SpongeBob is walking towards the picture of him and his parents to 2:40 when the picture is shown back to 9:00 clock when he "goes to look for more evidence."
In SpongeBob's idea of what happened to his parents, it shows that it is daytime, but when BlackJack comes in it is night.
In SpongeBob's idea of what happened to his parents, the stripe of Harold's hat is lighter than normal.
When SpongeBob is running to work on Uncle Captain Blue's car, the purple paint is still there from when he was painting Uncle Captain Blue's wall but when he is done fixing Uncle Captain Blue's car, the paint isn't there anymore.
When SpongeBob builds the fence, he builds it all around Captain Blue SquarePants' house, but when he drives SpongeBob to BlackJack's house, the fence has an opening.
When Uncle Captain Blue drives SpongeBob to BlackJack's house (who lives next door), the fence SpongeBob built earlier in the episode is brown, instead of white. BlackJack's house is not seen when he builds the fence however.
When Uncle Captain Blue drives SpongeBob to BlackJack's house, the grass around Uncle Captain Blue's house is replaced with sand.