Brain Drain

Brain Drain title card

Season 1, Episode 8
June 11, 2010
Supervising Producers
Production code

— Fanboy

Brain Drain is episode 8a of Fanboy and Chum Chum season 1.

After crash-landing when a stunt trick goes wrong, Fanboy loses his memory and is unable to remember everything well. Chum Chum has to find a way to bring Fanboy back to normal before Yo takes him home with her.


Fanboy begins by introducing to the show's audience his and Chum Chum's most mind-begoggling stunt ever: in which the Bathtub of Fury slides down the Stairway of Doom and goes up the Jump Ramp of Regret and lands in the Sponge of Spongyness. After going through a checklist of what they need, the boys prepare to start the sliding when Yo materializes in the back, happy to see Chum Chum. Fanboy wonders why Yo got here, and she explains she used a 12-years-in-the-future transporter cell phone given to her by her dad. Fanboy is interested at first, but then he tells Yo to get out of the tub as it's too heavy. Yo begins to make it lighter by de-materializing with Chum Chum in tow, but Fanboy stops her. Yo complains that she wants Chum Chum and Fanboy says she can't, as long as he has his brain, he won't let her have him. Yo says Chum Chum wants to be with her and, before de-materializing, menacingly says: "He just doesn't know it yet."

With Yo out of sight, Fanboy and Chum Chum carry on with their stunt and soon go flying in the air in the bathtub. In the middle of the trick though, the bathtub falls, leaving Fanboy and Chum Chum to float for a very long time. Chum Chum is happy he had his emergency parachute and pulls a cord on his underwear releasing it. Fanboy realizes he didn't put on his parachute after reading the note on his hand, and starts to fall at high speed. He notices a cord on his neck and pulls it, but that releases his brain, and he continues to fall.

Fanboy lands on the floor in the Fanlair, and his brain rolls under the couch. Chum Chum lands smoothly, stating that the stunt was awesome, only to hear a strange laugh from Fanboy. Fanboy begins acting dopey and bangs on the TV, mistaking it for a narwhal. Chum Chum wonders what happened and, upon noticing his head flap is open, looks inside to reveal that his brain is gone. After being mistaken for a narwhal, Chum Chum pickets to Fanboy that he is his best pal, but Fanboy does not remember this leaving Chum Chum shocked. Luckily, Chum Chum decides to go get a new brain for him from the fridge.

Chum Chum looks in the fridge and sees the replacement brain box, but it's not in there as Fanboy put the carton in the fridge after using the last one. Chum Chum then steps on the Sponge of Spongyness which gives him the idea to use that as a brain. He puts the brain in Fanboy's head and starts to teach him how to be himself again.

First, Chum Chum explains to Fanboy how much he loves Frosty Freezy Freeze, but Fanboy places the freeze on his head instead like a sandcastle. Then, when making his favorite food, toasted mayonnaise sandwich, Fanboy thinks the toaster is his food and starts to eat it, but Chum Chum corrects him stating that food goes in the mouth. Fanboy takes the sandwich and puts it in his head, thinking that's his mouth. Later, Chum Chum is playing checkers and anxiously waits for Fanboy's move, but all he does is bang pots and sing. Angrily, Chum Chum does the move for him yet again.

Yo re-materializes on Chum Chum's head and is successful at catching him, but is surprised at Fanboy not trying to stop her. Chum Chum explains that Fanboy lost his brain and is using the sponge to soak the memories back. Fanboy comes over and sees Yo, referring to her as "thing I don't know". After learning that it's Yo he's talking to, he tries to remember something about her but forgets it and goes off to show her his time tables (which is ruining the corn chip castle he and Chum Chum made). Yo, upon learning that Fanboy lost his brain, sees it under the couch and, upon getting an idea, hides it in her backpack.

Chum Chum comes back after putting Fanboy down for a nap and wonders if she needs something. Yo acts miserable and says Chum Chum is so hurt, lost and alone as Fanboy lost his brain. Chum Chum hopes Fanboy is not mad at the alarm clock again but is wrong as Fanboy thinks he can tell time by smashing it with a mallet. Yo decides to help out with Fanboy and thinks of moving in tonight, which surprises Chum Chum. Yo says that when she's living here, she can dress Chum Chum, brush his hair and dip him in chocolate, but rephrases herself and says she'll be here to help him. Chum Chum walks off to boil Fanboy some hot dogs for a mug of hot dog water after his nap while Yo chuckles to herself that Chum Chum is almost hers.

Fanboy notices a picture on the nightstand of he and Chum Chum, plus Yo trying to take Chum Chum while staring in surprise at the camera. This makes him remember something and angrily tells Yo what she's trying to do: get close to Chum Chum so she can take him. Yo distracts Fanboy with a ball of yarn and rings out the sponge, causing memory loss. And when Chum Chum comes back, he starts to cry that Fanboy is getting worse and thinks he's gone forever. Yo says they'll come back later and build a cage for Fanboy, but for now, she thinks Chum Chum will feel better if he comes home with Yo and sits on a shelf in a sailor suit.

As Yo begins to lead Chum Chum out, he notices her backpack is leaking and opens it, revealing she stole Fanboy's brain. Yo lies and says she found it under the Love Seat, but Chum Chum isn't fooled and they begin to fight over it. During this, Fanboy makes himself a sandwich using a wrench. Fanboy's brain suddenly slips out of Chum Chum and Yo's hands and lands on Fanboy's sandwich. He begins to eat it, but realizes food goes in mouth and puts the sandwich containing his brain into his head. This causes him to return to his normal self, and notices Yo leaving with Chum Chum. He spits out the sponge which hits Yo, and he takes back Chum Chum. Yo giggles and says goodbye, then de-materializes.

Chum Chum is happy that Fanboy remembers him, and Fanboy never forgets him as his best friend. The two hug, but Fanboy ends up squeezing Chum Chum so hard that his brain pops out, causing his incident as before to happen with Chum Chum as he mistakes him for a narwhal and trots away. Fanboy doesn't want to let Chum Chum deal with this alone and gets rid of his brain, and the two brainless boys act crazy together.


For a full transcript of Brain Drain, click here.


Your brain is gone!
The image gallery for Brain Drain may be viewed here.

Running Gags

  • Fanboy speaking in a low, dopey voice when his brain is gone.
  • Someone shouting "NARWHAL!".
  • Yo materializing and de-materializing thanks to her transporter cell phone.
  • Fanboy calling Chum Chum "Chirp Chirp".
  • When something is going on, Fanboy walks by in the background or foreground doing something else.
  • Every time someone's attitude changes due to a brain gain or loss, their eyes roll briefly.
  • Fanboy sliding his hand down Chum Chum's face.
  • Fanboy thinking his head flap is his mouth.


  • This is the first episode to feature only three voice actors. The second time is "The Tell-Tale Toy", and the third is "Get You Next Time".
  • This is the first episode where someone's parents are mentioned. In this case, Yo mentions her father.
  • First episode to take place at the Fanlair entirely.
  • Hank appears in this episode, but he does not say anything.
  • Near the end Fanboy calls Chum Chum "Chummerson". Maybe another hint towards Chum Chum's real name.
  • First time Fanboy is absolutely far from who he really is.
  • First episode where Chum Chum is the main character.
  • First time Chum Chum has more screen time than Fanboy.
  • Fanboy breaks the fourth wall by announcing the stunt to the audience at the beginning.



  • When Yo hears Chum Chum say her backpack is leaking, her eyelashes fall off. In the next shot and in the rest of the episode, her eyelashes are back.
  • When Fanboy is about to swat the phone away to stop Yo disappearing with Chum Chum, the teleportation effect starts to fade out before Fanboy stops her.
  • When Yo says "But I want him!" her mouth moves as if she were saying something else.
  • When Fanboy is about to turn back to normal, he is facing left, but when he is becoming himself again he is facing forward.
  • Yo finds a tag on Fanboy's brain that says "Property of Fanboy", but it was never there before.
  • After Fanboy turns normal again he sees Yo leaving with Chum Chum, but when he throws the sponge at her she isn't holding Chum Chum at all.
  • When Chum Chum starts to say "It's empty!" his mouth isn't moving.
  • The toasted mayonnaise sandwich is technically not a sandwich as it only has bread and mayonnaise and nothing else.
  • Chum Chum finds an emergency brain box in the fridge, but in every episode after, it's not there.
  • When Chum Chum steps on the Sponge of Spongyness, it is a few inches from the fridge and on the floor with no plate, but when they ride the course the sponge is next to the Ramp of Regret on a plate.
  • After the course is ridden the Ramp of Regret permanently disappears the rest of the episode.
  • The checkers game is designed wrong: it has 10 disks, 5 red and 5 black, and the board is 6x6. In real life, there are 24 disks, 12 red and 12 black, and the board is 8x8.
    • This is probably done because of the style of the show.
  • Chum Chum said he put Fanboy down for a nap, but Fanboy was not shown sleeping whenever the bedroom was shown.
  • Yo's backpack wasn't leaking in most scenes after she puts Fanboy's brain in it, but it appears when she turns around ready to lead Chum Chum out.


  • The Adventures of Jimmy Neutron, Boy Genius- The plot of the episode is somewhat similar to the episode "Normal Boy", as both plots involve the main character accidentally making himself less intelligent and begin acting more goofy and eccentric whilst the other character(s) tries/try to get him back to his normal intelligence level before something bad happens.
  • SpongeBob SquarePants- The Sponge of Spongyness looks pretty similar to the main character from the aforementioned series, minus the face, clothes, arms, and legs.
  • Psycho - After Yo sneakily says "He's almost mine!", a musical "sting" is heard in the background that is similar to what played during the shower attack scene in Alfred Hitchcock's Psycho.
  • Brain drain or Brain scape (Movie) - The title refers to the name of a Spanish movie in which 4 nerds with bad grades go to England searching love. Alternatively it might reference "The Brain Drain," the slide filled with soap which losers have to slide down on the Nickelodeon game show, BrainSurge.
  • Willy Wonka and the Chocolate Factory - When Yo cries out: "But I want him!" she is making a reference to Veruca Salt.
  • Star Trek - Yo's teleportation effects parody the same teleportation effects from Star Trek.


designates a character that did not appear in this episode
"Monster in the Mist"
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