- Lily Plankton (debut)
- Sheldon J. Plankton
- Eugene H. Krabs
- SpongeBob SquarePants
- Gary the Snail (cameo in picture)
- Miss Shell
- Old Man Jenkins (cameo)
- Mable the Gray Fish
- Miss Gristlepuss (cameo)
- Granny (cameo)
- Squidward Tentacles
- King Neptune (mentioned)
In the beginning at Shady Shoals Rest Home, Plankton is with his grandmother, who is lying down on a bed. After thinking of what to do with her, Plankton puts his grandmother to sleep, and then takes some of her clothes to wear.
Plankton later walks over to SpongeBob's house, where he appears. Plankton says that he is his great grandmother, in which he actually believes so. SpongeBob gives his "great grandmother" a tour of his house and shows Plankton all of his albums. The next day, Plankton wants to go to the Krusty Krab, but SpongeBob insists that they go to a nursing home instead. There, they knit and play cards, when Plankton rips a card in annoyance at SpongeBob's antics.SpongeBob realizes he is bored and decides to take him to the Krusty Krab, although Plankton says he wants to enter through the back door.
Meanwhile, Plankton ties up a balloon that looks like him. It flies away into the dishwasher, and when SpongeBob turns it on, the balloon pops. SpongeBob, thinking it is his great grandma, cries, but then Plankton re-appears and says he is fine. After, Plankton tells SpongeBob that he is tired and needs to take a nap in a private place. SpongeBob agrees and takes him to the safe. Thereafter, Plankton's grandma walks inside of the Krusty Krab and finds out what Plankton is secretly plotting. She takes him back while SpongeBob thinks that his own great grandma caught Plankton trying to steal the formula.
|( ‣ ) Associated production music|
|( • ) Original music|
|( ◦ ) SpongeBob music|
‣ Unknown Track 1 - Sage Guyton, Jeremy Wakefield [Title card]
‣ Happy Home - Harry Bluestone, Emil Cadkin [opening at Shady Shoals]
‣ Epic Struggle - Fredric Bayco [Plankton puts his grandma's teeth in his mouth]
‣ Sweet and Lovely - Alan Braden [Plankton's daydream]
‣ Dramatic Impact 6 - Ivor Slaney [Plankton laughs evilly]
‣ Salty Squid Jig - Michael Bolger, Nicolas Carr, Sage Guyton, James King [SpongeBob taking a bath]
‣ Sea Battle [#45] - John Fox ["Threat neutralized, Captain."]
‣ Sea Battle [#48] - John Fox ["Uh-huh. Right away, Captain. All hands, prepare to dive!"]
‣ Steel Link (a) - Jeremy Wakefield [SpongeBob answers the door]
‣ My Three Fish - Barry Anthony [Plankton disguised as an old lady]
‣ Harp Ding - Nicolas Carr [SpongeBob gets an idea]
‣ Steel Sting (v) - Jeremy Wakefield [Plankton stuck in the pillow]
‣ Hawaiian Party - Peter Dennis [looking at old photo albums]
‣ Steel Sting (b) - Jeremy Wakefield [the next morning]
‣ Tiptoe Through the Seaweed - Nicolas Carr, Barry Anthony [SpongeBob wakes Plankton up]
‣ Crescendo Fin 10 A - Marcin Pospieszalski [Plankton laughs]
‣ Holiday Playtime - Cedric King-Palmer [Plankton puts on lipstick]
‣ Lambs in Clover - Jack Strachey [Grandma's Tea House]
‣ Cocksure Capers - Phil Green [card game]
‣ Domestic Fun (a) - Ernest Tomlinson [SpongeBob takes Plankton to the Krusty Krab.]
‣ Domestic Fun (c) - Ernest Tomlinson [Plankton screams]
‣ Cartoon Sting 1 - "You have been warned about lurking back here on your days off."
‣ Vibe Sting - Nicolas Carr [Plankton's gone]
‣ Cartoon Sting 1 - Squidward taking out the trash
‣ Domestic Fun (b) - Ernest Tomlinson [Plankton in the garbage can]
‣ Nautical Hijinx - Nicolas Carr, Barry Anthony [SpongeBob takes Plankton into the kitchen]
‣ Apprehensive 2 - Harry Bluestone, Emil Cadkin [Plankton inflates decoy]
‣ Nautical Hijinx - Nicolas Carr, Barry Anthony [SpongeBob turns on the garbage disposal]
‣ Dramatic Impact 5 - Ivor Slaney ["GRANDMA!"]
‣ Epilog - Gerhard Trede [SpongeBob crying]
‣ Vibe Q Sting - Nicolas Carr ["SpongeBob, up here!"]
‣ My Three Fish - Barry Anthony [SpongeBob puts Plankton in Krabs' safe]
‣ ? ["Sweet dreams, Grammy-Ma."]
‣ Zelle 501 - Gerhard Trede [Plankton finds the formula]
‣ Dramatic Impact 6 - Ivor Slaney [Plankton gasps]
‣ Unknown Track 1 - Sage Guyton, Jeremy Wakefield [Ending]
- This episode is available on the SpongeBob's Frozen Face-Off (UK version only), Complete Seventh Season, and Next 100 Episodes DVDs.
- As of August 19, 2016, The Internet Movie Database (IMDB) gives this episode a rating of 6.5/10 based on 85 ratings by users. TV.com users give this episode a rating of 7.6/10 based on 62 votes.
- Miss Gristlepuss from "Banned in Bikini Bottom" and Granny from "Have You Seen This Snail?" appear while SpongeBob and "Great Grammie Ma" are knitting.
- Irony: It would have made more sense for Plankton to steal the formula himself (like in his vision) than to pretend to be SpongeBob's grandma.
- SpongeBob said a similar line in "Gone," when he said, "So it was true..."
- This episode premiered on Burt Ward's 65th birthday.
- Lily Plankton reappears in the episode "Grandmum's the Word."
- In the opening and closing credits, Laraine Newman's name is misspelled as "Loraine Newman."
- This episode says that when SpongeBob was a baby, he was a yellow blob, but in several other episodes (such as "Goo Goo Gas" and "Friend or Foe"), he's just smaller as a baby kitchen sponge.
- When Plankton pulls down his antennae, they are quickly stuck back up when SpongeBob and Plankton are walking together.
- Gramma Plankton calls her grandson "Plankton," when she should be calling him "Sheldon" as "Plankton" is the family name.
- At the end of the episode, she also calls him "Plankton Jr."
- A similar error also occurs in "Stanley S. SquarePants."
- When Plankton is turned into a scarf, he has two eyes.
- There is chocolate on the pillow and blanket, but when Plankton laughs, it is gone.
- In the original American airing, after Plankton steals his grandma's clothes and hair, she still has hair, but at the end, she is bald when she comes to take it back. The error was later fixed in American re-runs and on the season 7 DVD release.
- However, this is unfixed in some countries, as like Israel, Croatia, Poland, and Germany.
- Whenever Plankton takes off the glasses, his one eye disappears when he puts them back on and off.
- The balloon "Grammie Ma" should have popped when it went in the garbage disposal, but is slowly cut up.
- When SpongeBob and Plankton play cards, the animation cell for the table in the background is above SpongeBob's, so parts of his left hand are erased multiple times when it goes near the table.