Spoiler warning! This article contains plot details about an episode you may not have seen. Read with care!
Plankton is the seventh episode of the award-winning series, Spongebob Squarepants. It begins with SpongeBob and Squidward Tentacles working at the Krusty Krab. After SpongeBob puts a Krabby Patty under Squidward's nose, it dances and heads toward the front door. SpongeBob calls for Mr. Krabs, telling him that the Krabby Patty is haunted. Mr. Krabs catches the patty and discovers it is being driven by Plankton, whom in his first appearance is trying to steal the Krabby Patty formula. Mr. Krabs confronts Plankton, who storms off. After work, SpongeBob meets Plankton, and Plankton tells SpongeBob that the next day was his birthday. SpongeBob discovers Plankton's trick to give him the secret formula for his birthday and goes home even when Plankton offers him a golden spatula. Then, Plankton sneaks into SpongeBob's House in the middle of the night and takes control of SpongeBob's brain. Plankton wakes SpongeBob up and forces him to go to Squidward's House. There, the helpless SpongeBob destroys Squidward's bedroom, and Plankton calls him a mediocre clarinet player. Next, SpongeBob is forced to venture over to Patrick's House. SpongeBob destroys the rock and leaves a sleeping Patrick lying on the ground. Afterward, SpongeBob is taken to the Krusty Krab and takes a Krabby Patty from there to Plankton's Chum Bucket. SpongeBob tries to resist Plankton but is ultimately taken to the lab. There, an analyzer, Plankton's wife, Karen, examines a piece of seaweed as 50% Sea; 50% Weed. SpongeBob laments his defeat and goes over the delicious ingredients of the formula, making Plankton's mouth water. Eventually, he jumps out of SpongeBob's brain and onto the Krabby Patty but slips off the bun and into the analyzer. It describes him as 1% Evil; 99% Hot Gas. SpongeBob walks out of the Chum Bucket with the battered Krabby Patty to end the episode.
This is the 3rd time Sandy doesn't appear and her 2nd straight missed segment.
This marks the 5th appearance of both Squidward and Patrick.
This is the 7th appearance of SpongeBob SquarePants.
This is the 1st time Mr. Krabs appears since the pilot episode, Help Wanted.
This is the 1st appearance of Plankton and Karen, who are voiced by Doug Lawerance and Jill Talley, respectively.
This episode was released on the Lost At Sea DVD/Video.
This is the 2nd appearance of Gary. Like Krabs, it is his first since Help Wanted.