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." Grandma SquarePants soon appears and tells him that BlackJack had recently called her.
SpongeBob seeks help from his uncle, Captain Blue SquarePants, a retired police captain. 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.
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In the episode, the pineapple in which SpongeBob lives in was just referred to as "The Pineapple, Bikini Bottom," instead of 124 Conch St. This happened again in "Pet Sitter Pat."
The return address that has been covered by saliva can be made out as "BlackJack, 133 Coral Rd or Bd, Bikini Bottom."
The door knocker on BlackJack's house has a hand attached to it with a bone sticking out. This hand resembles SpongeBob's hand.
Uncle Captain Blue's boat is able to be driven in SpongeBob's Boating Bash.
Blackjack being sent to jail over littering makes sense, as the Bikini Bottom police treat littering very seriously: in "Summer Job," Mrs. Puff was sentenced to 2,529 days of prison just for littering, and in "Driven to Tears," even though Patrick commits several moving violations, yet he's only charged with littering. In "Keep Bikini Bottom Beautiful," Squidward was sentenced to community service for getting rid of gum that had gotten stuck to one of his "leg" (tentacles).
SpongeBob regenerates body parts again. This time, he regenerates the legs he used to break through the plastic.
This episode features more appearances of SpongeBob's relatives than any other episodes with a total of five characters.
When SpongeBob flashes back to when he was a kid, he is wearing a bow tie. This might be the same bow tie that he wore in "Squirrel Jokes."
When SpongeBob is at his parents' house, there are pictures of fish, as they are most likely their friends, but this has not been confirmed.
Grandma's house also has similar pictures.
In SpongeBob's idea of what happened to his parents, his parents are fancy looking. They shouldn't be because they are just relaxing at home. However, this may not be an error, but just that SpongeBob's most recent memory has them in those clothes, which is him holding the picture of him and his parents.File:Bowl.pngBlackJack (Left) and Grandma's Kisses (Right)
The bowl on Grandma's counter is the same as the one in "Grandma's Kisses" with a different, more clearer shape.
Cultural references
BlackJack is a reference to the card game of the same name "Blackjack."
Errors
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.
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.
In SpongeBob's idea of what happened to his parents, it shows that it is daytime, but when BlackJack comes it is night.
In SpongeBob's idea of what happened to his parents, the stripe of Harold's hat is lighter than normal.
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."
When SpongeBob is running to Uncle Captain Blue's car, the purple paint is still there from when he was painting Uncle Captain Blue's car but when he is done fixing Uncle Captain Blue's car, the paint isn't seen.
In Home Sweet Pineapple, SpongeBob says "goodbye Bikini Bottom" implying that his parents don't live in Bikini Bottom, yet in this episode, it is in Bikini Bottom.