|Full Name||The Brain|
|Segment||Pinky and the Brain|
|First Episode||The Monkey Song/Win Big|
|Voice Actor||Maurice LaMarche|
|Catchphrases|| "Are you pondering what I'm pondering?"|
"Stop it, Pinky, or I shall have to hurt you."
"The same thing we do every night Pinky, try to take over the world."
The Brain is an intelligent megalomaniac mouse that harbors a long-lasting desire to take over the world. He is often annoyed by his cage-mate Pinky’s silliness, but it doesn't stop him from hatching up complicated schemes each night in order to achieve global domination. How ever he notes that since he was really smart that he could make the world a better place.
In You'll Never Eat Food Pellets In This Town Again, Brain has a wife named Sheila who apparently plays Billie. However, this episode was non-canonical and was meant to poke fun at WB's petty executives. Brain is heavily based on Orson Welles in both looks and vocal performance. In one episode he even tried to copy Orson's infamous radio telling of War of the Worlds.
Character infoThough he is extremely intelligent, he often misses a fatal flaw or makes a small mistake that causes the plan to completely fail. Though he never admits fault and blames Pinky for his failed attempts at world domination, he genuinely cares for him. There are a few occasions that have been completely out of his control reasons why his plans don't work.
The Brain was originally a wild mouse, but was captured at a very young age and brought to ACME, where he was placed in a cage with Pinky. The two of them grew up together, and Brain's trauma caused him to strive for world domination. He also spent some of his younger years with Snowball prior to the hamster’s turn to the dark-side. Though exact details of the origin story varies throughout the series, these are the constant elements in all of them.The closest he ever came to world domination was in the Christmas special. He had managed to use Santa to deliver mind control dolls to every home in the world; however, as he was about to give the signal through the dolls the spirit of Christmas overtook him (after reading Pinky's letter to Santa Claus) and he instead ordered the world to have a merry Christmas.
In Wakko's Wish, he fulfills his desire to rule the world (or at least be in charge of a small part of it) by becoming the prime minister of ACME Falls. He states in the end that he plans to take over the world in the sequel. There was unfortunately no sequel to the film.
Brain is bitter, rude, short-tempered, clever, self-centered, scheming, angry, irritable, grumpy, sarcastic and deadpan, but he has a soft and tender heart. He is often aggravated by Pinky's dim-witted comments and claims he's going to hurt him if he doesn't stop - a threat he quite often follows through on. On rare occasions throughout the show, it becomes increasingly obvious he does care for Pinky. The sentiment, however, is usually overshadowed by Brain's ambition for his most recent scheme. Maurice LaMarche has teased that in the Animaniacs reboot, Brain will become even more bitter as he still hasn’t taken over the world after all these years since the original shows ended (go to around 14:23-ish). 
Brain was, for the most part, based on the famous actor Orson Welles. Actor Maurice LaMarche did add, on a couple of occasions, that Brain is 65% Orson Welles and 35% Vincent Price.
The Brain has also been shown to shed tears a few times, such as after reading Pinky's letter to Santa in "A Pinky and the Brain Christmas", a letter which Pinky didn't get the chance to deliver. The letter stated that all he really wants is for his best friend, The Brain, to be happy. This makes Brain realize how much of a true and loyal friend Pinky is, and that perhaps there's more important things in life than world domination - at least on Christmas.
- Main Title (nonspeaking)
- Ep1: The Monkey Song (nonspeaking)
- Ep1: Nighty-Night Toon (supporting)
- Ep2: Pinky and the Brain Intro #1
- Ep2: Win Big
- He hates being chided. In addition, he also dislikes the unexpected, cameos, the sea, leeches, clowns, Snowball; simply put they're all the worst.
- Sadly and ironically, he doesn't see just how much he bullies Pinky. In "Cute Little Alienhead" (Pinky, Elmyra and the Brain), Brain gets a taste of his own medicine when the alien he has contacted starts calling him dummy boy, which angers Brain to no end. Not only that; Pinky gets in a return volley by insisting, "Aliens aren't the only ones who want to know they're valued, you know!"
- He has a beautiful singing voice, which he denies in "Brain's Way".
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A Meticulous Analysis of Why Brain Fails
All of Brain's attempts to take over the world fail. There is more than one reason for this. These reasons simply consist of three basic categories.
Category One: There may be a flaw in his flawless plan that he forgot to factor in, and it isn't discovered until it's either too late to fix or the plan has already blown up in his face. For example, in the episode Opportunity Knox he forgot that gold is extremely heavy. Too heavy for a mouse to carry.
Category Two: Pinky has a natural knack for screwing things up. When he's involved in the plan's execution, expect to bear witness to a mess in the making. An example of this would be in the episode Brain Meets Brawn where Pinky had to apologize for making a mistake.
These first two reasons were explored by Brain in the episode That Smarts, in which he addresses the issues surrounding his plans' failures and builds a machine that has the ability to either increase or decrease intellect. Before using it on Pinky, Brain tells Pinky that he has done some research and has found that Pinky himself is the reason for all of Brain's failures. After using it on Pinky, Pinky becomes very smart. However, by making Pinky really smart, it changes everything about their relationship and makes it so boring. The relationship between the two mice then becomes strained as Brain tries to find a reason as to why his discovery failed and it was also due to Pinky's belief that Brain didn't like him anymore because he became very smart. In the end Pinky reverts himself back to his simple minded ways once he drains his brain and Brain figures out that he, himself is the true reason to blame for his failures. The last few seconds of the episode show the two mice having turned themselves into dummies by the use of the machine.
Category Three: Sometimes it's merely a matter of circumstance, and neither of the mice are at fault. Something or someone interfered with their plans.
Category Four: A mix of elements of all three (usually the first two).
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