Encyclopedia SpongeBobia
Encyclopedia SpongeBobia
If you were looking for the article about the character, then see Virus.

"Karen's Virus" is a SpongeBob SquarePants episode from Season 11. In this episode, Karen gets a computer virus, and it's up to SpongeBob to get it out of her.



The episode starts with Karen obtaining a virus due to hanging out with a sick computer. Plankton sees this and needs someone stupid enough to want to fix her, and just at the right time, SpongeBob is next to the Chum Bucket. After deciding that the mission will be called "Operation: Save Karen," Plankton transports SpongeBob into Karen to defeat the virus.

Plankton gives SpongeBob directions on how to find the virus and soon after he starts looking for it, he falls down into a hole the virus made and sees it eat through Karen. Meanwhile, Karen becomes completely delusional and escapes the Chum Bucket into the Krusty Krab, where she causes chaos. SpongeBob flings back up onto the surface of the inside of Karen and continues searching for destruction caused by the virus, but accidentally activates the security button. Thankfully, before he gets shot by a laser, he is saved by Ideal Plankton, who is what Karen pictures Plankton as.

As the virus continues destroying parts of Karen, Ideal Plankton and SpongeBob confront different characters how Karen sees them, and gets into a battle with them. After they defeat them, the two see the virus on the other side of a trench. SpongeBob uses a rope to cross the trench, but when Ideal Plankton tries to cross, part of the ground breaks and he falls into the trench, forcing SpongeBob to have to save Karen by himself.

Karen is shown driving a car to a party at Wagon Wheel due to how delusional she is. Inside Karen, the virus is shown to be eating Karen's memories, prompting SpongeBob to try and defeat it. After his attempts fail, he gets so scared he breaks into pieces. When he goes back into normal form, he winds up with one extra piece and throws it onto the ground. The virus eats this, telling SpongeBob that the virus is simply hungry. The episode ends with SpongeBob taking out the virus from Karen and letting him eat a Krabby Patty to satisfy how hungry it is.


The episode was confirmed by Vincent Waller on March 29, 2018.[1]

According to Dave Cunningham, in a Q&A with Encyclopedia SpongeBobia, the episode took longer to produce than normal and he, Sherm Cohen and Adam Paloian asked colleagues to give more time if they felt they needed it - "it paid off".[2]



 ) Associated production music
 ) Original music
 ) SpongeBob music

  One Zero Zero - Harry Breuer, Jean-Jacques Perrey [Title card]
  Happy Links 6-9 - Paul Fenoulhet [Karen and Hanna at the Chum Bucket]
  Happy Links 1-5 - Paul Fenoulhet [Karen sneezes at Plankton]
  A Series of Unfortunate Events - Nicolas Carr [Karen malfunctions]
  Hot Steel and Slide Licks 13B - Jeremy Wakefield ["Uh-oh."]
  Hot Steel and Slide Licks 20C - Jeremy Wakefield ["My ones and zeroes look like 10, 10, 10, 10."]
  Mission Improbable - Nicolas Carr, Barry Anthony ["Someone's gonna have to get inside you and kill that virus."]
  Seaweed 2 - Steve Belfer [SpongeBob knocking Chum Bucket door]
  In Disguise Ensemble - [ProjectSAM Symphobia Colours: Animator] [Plankton tells SpongeBob that Karen needs his help]
  Phrases - Is It Jazz - [ProjectSAM Symphobia Colours: Animator] ["♪Who lives in a crabapple under a pea♪"]
  Lap Steel - Nicolas Carr [Transition to next scene]
  Phrases - Is It Jazz - [ProjectSAM Symphobia Colours: Animator] ["♪Observant and yellow fellow is he♪"]
  Pedal to the Metal - Nicolas Carr ["Journey to the Center of Karen."]
  Arnold is Back 2 - Gregor Narholz ["The Mainframe Mission."]
  Great Idea Patrick - Nicolas Carr ["Ooh, I know!"]
  Glory Road - Sam Fonteyn ["Operation: Save Karen!"]
  Toy Piano 2 - Nicolas Carr, Barry Anthony [SpongeBob holds up a drawing]
  Hot Steel and Slide Licks 1A - Jeremy Wakefield [Chum Bucket exploded]
  Very Funny - Nicolas Carr [Plankton blows the fire out on his antennas]
  Neutral Mood - Simon May [SpongeBob zapped and injected into Karen]
  In Disguise Ensemble - [ProjectSAM Symphobia Colours: Animator] ["Get away."]
  Uh Oh Flutter-Eyed - [ProjectSAM Symphobia Colours: Animator] [Plankton gets electrocuted]
  Space Trek - Philip Johnston, Norman Whittle [SpongeBob arrives at Karen's hard drive]
  Destination Unknown - Gregor Narholz [Plankton starts talking to SpongeBob via megaphone]
  Lighten Up a Little - Nicolas Carr ["Talk to me, you digitized doofus!"]
  Destination Unknown - Gregor Narholz [Plankton tells SpongeBob to look for destruction]
  Monster Movie Orchestra - Steve Sechi, Kostas Varotsis [SpongeBob falls through a hole made by the virus]
  Monster Bug A - Gregor Narholz [Karen gets off the table]
  Melodramatic Moments - Michael Bolger, Nicolas Carr ["I need you to control your wife. Er, computer, or whatever."]
  Hot Steel and Slide Licks 8B - Jeremy Wakefield [Karen throws Squidward away]
  Melodramatic Moments - Michael Bolger, Nicolas Carr [Krabs grabs the cash register out of Karen]
  Hot Steel and Slide Licks 32B - Jeremy Wakefield ["Wow, I can never un-see that."]
  Code "Dead End" - Gregor Narholz [SpongeBob wandering through the hard drive]
  Odyssey - Sam Spence [Ideal Plankton appears and blasts the lasers with a laser gun]
  Comedy Punctuations and Bridges 3 - Fredric Bayco [SpongeBob sighs and skips]
  Fun of the Fair - David Farnon [Amusement park in Karen's hard drive]
  Musique De L'Infini - Jean-Jacques Perrey [Virus destroys Karen's anger control center and love center]
  Odyssey - Sam Spence [Ideal Plankton climbs up a wall with SpongeBob]
  Unknown Track 72 - Money Krabs appears
  ? [Gnarly Squid appears]
  Hot Steel and Slide Licks 15 - Jeremy Wakefield ["Hmm? Uh, nothing like a little make-up couldn't fix."]
  ? [Off Model SpongeBob appears]
  Armed Attack - Jean Clero [Ideal Plankton fights Money Krabs and Gnarly Squid]
  ? [Both SpongeBobs babbling]
  Code "Dead End" - Gregor Narholz ["Neptune's network! Which one of you is the real SpongeBob?"]
  Unknown Track 72 - SpongeBob claps
  Musique De L'Infini - Jean-Jacques Perrey [Virus roars to SpongeBob and Ideal Plankton]
  Thrill Ride - Gregor Narholz [SpongeBob swings across a ravine]
  Tower of Evil - Magnum Opus [Ideal Plankton falls into the ravine]
  Odyssey - Sam Spence ["I mean, yes!"]
  SpongeBob Theme II - Nicolas Carr, Sage Guyton, Jeremy Wakefield [Karen driving crazily a boat with Plankton]
  Hillbilly Party - Nicolas Carr, Sage Guyton, Jeremy Wakefield [Karen crashes the boat into Wagon Wheel]
  On Fire - Gregor Narholz [Virus at Karen's memory bank]
  New Vibe Hits 2007 - Nicolas Carr ["I always wind up with one extra piece."]
  One Zero Zero - Harry Breuer, Jean-Jacques Perrey [Virus eats SpongeBob's extra piece]
  Hot Steel and Slide Licks 12 - Jeremy Wakefield [Karen is tired and shuts off]
  Earl's Revenge - Sage Guyton, Jeremy Wakefield [Ending]




  • This episode's title card uses the same music track, "One Zero Zero," as the title card for The Mighty B! episode, "Bee Patients."
  • This and "Girls' Night Out" are the first episodes to premiere on a day that daylight saving time ends in the United States.
  • This episode was paired up with "Girls' Night Out" during the original American airing, but has since been re-airing with "Appointment TV."
  • SpongeBob binary code on Karen's screen.

    On the computer with a broken screen, it shows "01010011 01110000 01101111 01101110 01100111 01100101 01000010 01101111 01100010 00100000 01010011 01110001 01110101 01100001 01110010 01100101 01010000 01100001 01101110 01110100 01110011", which is a binary code for "SpongeBob SquarePants".
  • In the UK, Plankton's line, "It's probably a suicide mission" was removed due to "suicide" being an inappropriate word.[3]
  • Karen breaks the fourth wall when she sings a warped version of the SpongeBob SquarePants theme song in her delusional state.
    • This is the fifth episode to reference the show's theme song within an episode, after "Truth or Square," "Unreal Estate," "Sanitation Insanity," and "Old Man Patrick."
      • Also, in all of the episodes, SpongeBob is always shown calling the theme song a "Catchy song," meaning that he can possibly know the existence of his theme song.
    • Karen is the first main character other than SpongeBob to sing the song.
  • This episode was originally going to premiere on October 24, 2018, but due to Brian Robbins appointed to be the new president of Nickelodeon, it was delayed to November 4, 2018.[4]
  • When SpongeBob gets mixed up after he is charred by the virus, he resembles how he does at one point in the theme song sequence.
  • Lily Plankton makes a cameo in a picture.
  • The flashbacks in Karen's memory includes footage from "Plankton!," "Welcome to the Chum Bucket," "The Algae's Always Greener," "Plankton's Army," "Enemy In-Law," "Komputer Overload," "Salsa Imbecilicus," "Plankton Gets the Boot," and "F.U.N."
  • The fourth wall is broken twice in this episode:
    • Karen throws a boat in the sky, hitting and knocking down one of the flower clouds.
    • Karen sings a warped version of the theme song in her delusional state.
  • This marks the first usage of the APM track "On Fire" since "Banned in Bikini Bottom."
    • This also marks the first usage of the track "Arnold is Back 2" since "Patty Hype."
  • This is the second SpongeBob SquarePants production that involves CGI, in this episode, it is inside Karen. The first production was The SpongeBob Movie: Sponge Out of Water.
  • This episode marks the first appearance of SpongeBob's karate gear since the season 9 episode "Sandy's Nutmare."
  • The lady touches Plankton's rear happened to him back in "Salsa Imbecilicus" from going in Patrick's mouth and got licked by his tongue.
    Karen virus german.png
  • In the German dub, this episode is titled "Karens Virus," without the apostrophe, making the title card of the German dub almost identical to the original English version.

Cultural references