Characters: The Adventures of Jimmy Neutron: Boy Genius
James "Jimmy" Isaac Neutron
Voiced by: Debi DerryberryThe main protagonist. He is a boy with a stunning IQ and a love for science. From Hypercubes to Hypnorays, Jimmy can whip up the most amazing inventions. However, things have a way of going awry, and more often than not, Jimmy has to save the day from himself. But with friends, family, and a secret lab, there's no problem this boy genius can't handle. Right?
- Aesop Amnesia: At least half of the episode plots wouldn't happen if Jimmy would remember how often his inventions backfired.
- Anime Hair: Lampshaded consistently.
- Belligerent Sexual Tension: With Cindy.
- Berserk Button: Do NOT give Jimmy an F. Denzel Crocker in the Jimmy Timmy Power Hour learns this the hard way.
- Big Damn Heroes: ALL THE TIME. Often Lampshaded, in fact.
- Big "NO!": In The Tomorrow Boys, after learning he gets married to Cindy. In a bit of Leaning on the Fourth Wall, the scream cuts to a commercial. When the show comes back on, Sheen comments that he had been screaming for four minutes straight.
- Black Sheep: In one episode, most of the Neutron extended family views him as such, correctly pointing out that, while Jimmy may have saved the day quite often, more often than not, it was one of his inventions that caused the problem in the first place.
- Brilliant but Lazy: Why do something as simple as neatly put away your piles of pants when you can implant chips in them that do it for you? Carl and Sheen call him out on this, though.
- Butt Monkey
- Cassandra Truth: In the episode, "The Eggpire Strikes Back", no one believes Jimmy when he says that the Yolkians, the villains from the pilot film, are still just as evil as ever, until Poultra is bearing down on him.
- Catch Phrase: Originally "Gotta blast!" "Think, think, THINK!" and "Brain blast!". The show eased off on these as it went on, eventually getting rid of them entirely. (One exception is "And now, my latest invention, the (insert plot-related-device here!)", which stayed for most of the series' run.)
- Child Prodigy
- Comic Trio: He's the straight man.
- Crazy-Prepared: His watch, whose powers depend mainly on the plot. Can include lasers, freeze rays, magno-rays, GPS, tracking devices…you name it, there's probably a gadget for it tucked away in there.
- Cross Dressing Voice
- Deadpan Snarker:Jimmy: *science babble about a spider*Sheen: Fascinating! Can you make it do the hokey pokey?Jimmy: Sheen, go home.
- Fatal Flaw: Jimmy's greatest flaws are a combo of Pride and his lack of common sense; in fact, many of the conflicts in the show are born out of this.
- Future Loser: In the 'Bad Future' of The Tomorrow Boys, Future!Jimmy is a slack-jawed loser, wanted by the evil dictator Libby, with a five-o'clock shadow and Cindy as a wife. Current!Jimmy is less than impressed.
- Gadgeteer Genius
- He Cleans Up Nicely: When Jimmy shows up in a tux for Jet Fusion's wedding to Beautiful Gorgeous in My Big Fat Spy Wedding, Cindy promptly gets little hearts in her eyes.Cindy: "So Neutron's the best man? Yeah, more like the best NERD! I bet he'll look like a total…" (Jimmy shows up outside the church in a tux. Cue fade to pink background, eye-hearts and hair patting) "…HUNKMUFFIN."
- Another example is during Love Potion #976-J, when Jimmy cleans up for his date with Cindy. Said almost word-for-word by Cindy.
- "Hell Yes" Moment: Often. Especially when he's given up all hope... and then his friends forgive him for being arrogant/apologize for being stupid/come back to save him.
- The Hero
- Insufferable Genius: At times, but often more pronounced when Cindy's around.
- Intelligence Equals Isolation
- Kid Hero
- Little Professor Dialogue: Justified partially in that he does actually have an IQ of 210.
- Nice Job Breaking It, Hero: 99 out of 100 times, his inventions end up causing problems for everyone in Retroville, leading him to fix what he broke. As revealed in one episode, the majority of the Neutron extended family views him as the Black Sheep as a result.
- Pet's Homage Name: Jimmy designed and built his robot dog and named him Goddard in honor of rocket science physicist and inventor Robert Goddard. Especially apt when, in his first animated feature film, Jimmy is able to ride upon Goddard like a space bike.
- Puppy Love: With Cindy.
- Ridiculously Successful Future Self: In the 'good future' of The Tomorrow Boys, Jimmy is the first person to ever win the Nobel Prize in bulk.
- Rival Turned Evil: In The N-Men...
- Science Hero
- Sesquipedalian Loquaciousness: A frequent user and abuser.
- Slap-Slap-Kiss: With Cindy. All the time.
- The Smart Guy: Duh.
- Took a Level in Dumbass: When he accidentally drained his brain too much in Normal Boy.
- TV Genius
Carlton "Carl" Ulysses Wheezer
Voiced by: Rob PaulsenJimmy's shy, asthmatic best friend who has an unhealthy obsession with llamas and Jimmy's mom.
- The Chew Toy
- Comic Trio
- Cowardly Sidekick
- Big Eater: You'd think having so many allergies would limit this, but no. Carl can chow down with the best of 'em and has a stomach of steel. Occasionally overlaps with Extreme Omnivore for laughs:Carl: I don't eat newspapers! (Beat) Well, I'm trying to quit.
- Fat Best Friend
- Fartillery: Gets this in "The N-Men" (see Gasshole below).
- Gasshole: He has burped more than anyone else on the show (except for Jimmy's dad). In "The N-Men", he gets hit by some cosmic radiation that turns him into "Belch Boy", allowing him to unleash sonic blast burps by drinking seltzer or shaking himself really hard.
- Green-Eyed Monster: Implied quite heavily in "I Dream of Jimmy" and "Carl Wheezer, Boy Genius" that he'd really like to have Jimmy's life.
- The Heart
- Likes Older Women: Carl has a crush on Jimmy's mom since Love Potion #976-J.
- He's also attracted to the class's teacher, Miss Fowl, who's in her fifties. At least.
- Loose Lips: Sheen helps him a lot with this one. They're often the ones to reveal the secret plan to the enemy, generally via Suspiciously Specific Denial.
- Nerd Glasses
- Nerdy Inhaler
- Precocious Crush: On Jimmy's mom.
- Shrinking Violet
- Sickly Neurotic Geek: What else can you expect with a surname like 'Wheezer'?
- Stalker with a Crush
- Took a Level in Jerkass: Carl takes it in "Carl Wheezer, Boy Genius", which starts out as a standard "I lied to my pen pal" farce, then quickly escalates as we learn Carl lied about having Jimmy's life. It goes downhill as Carl not only has to masquerade as a boy genius, but he forces Jimmy to be his "lowly assistant", berating and constantly screaming at him for all his mistakes. Even by the end, when Jimmy has saved his life at least three times, Carl is still screaming at him... and projecting his own insecurities onto Jimmy to boot.
Sheen Juarrera Estevez
Voiced by: Jeffrey GarciaJimmy's hyperactive other best friend who is obsessed with the comic book superhero Ultra Lord.
- Accent Adaptation. In the Latin American dub, he speaks with a Japanese accent, possibly because the translators thought that he's Japanese-American, instead of Hispanic, and his name should be pronounced "Shin".
- Beta Couple: With his sweet princess, Libby.
- The Big Guy
- Cloudcuckoolander: In a minor but interesting play off of the idiot sidekick shtick. Sheen isn't exactly stupid (at least before Flanderization set in); he's just very, very scatterbrained.
- Comic Trio
- The Ditz: His IQ is 32.
- Drunk with Power: When his intelligence is increased in Sheen's Brain.
- Early Installment Weirdness: He mentions a sister in "I Dream of Jimmy" but Word of God has said since to disregard it. Canonically, Sheen is an only child who lives with his father and grandmother (at least until Planet Sheen).
- Extraverted Nerd
- Goofy Print Underwear: Limited Edition Ultra Lord Underwear! Only available in Japan!
- Hollywood Tone-Deaf: His singing is so bad, it actually puts the music-hating Twonkies to sleep.
- Loony Fan: He's obsessed with cartoon superhero Ultra Lord.
- Loose Lips: See above.
- Missing Mom
- Plucky Comic Relief
- Puppy Love: With Libby.
- The Slacker
- Spin-Off: Gets his own one of these, Planet Sheen.
- The Watson: Has his moments.
Cynthia "Cindy" Aurora Vortex
Voiced by: Carolyn LawrenceJimmy's rival who has a crush on him. Not that she'll admit it.
- Academic Alpha Bitch
- Action Girl
- Bare Your Midriff: As Special Girl.
- Belligerent Sexual Tension: With Jimmy.
- Blondes Are Evil: While not evil per se, she can be a real Jerkass.
- Cannot Spit It Out: More because of pure stubbornness than anything, really.
- Clingy Jealous Girl: She doesn't like seeing Jimmy showing interest in other girls.
- Deadpan Snarker
- Defrosting Ice Queen
- Genius Bruiser
- Girlish Pigtails: In the movie.
- Goofy Print Underwear: Polka dot panties.
- Green-Eyed Monster: At least part of her problem with Jimmy stems from this. In The Movie, she says that before Jimmy came along, she was the smartest kid in school. It's a given that she didn't appreciate being knocked down to number two.
- Hair of Gold, Heart of Gold: She really does care about Jimmy deep down, though she's more in the disguise of Jerk with a Heart of Gold.
- Hint Dropping: Unfortunately, Jimmy seems to permanently be holding the Idiot Ball when it comes to interpersonal relations.
- Hypnotize the Princess: Gets hit with this in the Halloween special, courtesy of Vampire!Carl.
- I Know Karate: She actually says this in "King of Mars."
- Kung-Fu Kid: Cindy practices karate. She goes to competitions, is sometimes seen in her gi, and although we're never told what level she's at, based on some of her flips, she's probably a black belt.
- The Lancer
- Loving Bully: She picks on Jimmy but she only does this to mask her love for him.
- Puppy Love: With Jimmy.
- The Rival: To Jimmy.
- Slap-Slap-Kiss: With Jimmy. Are you starting to get an idea of their relationship yet?
- Tomboyish Ponytail: In the TV series.
Liberty "Libby" Danielle Folfax
Voiced by: Crystal ScalesCindy's best friend. The love of Libby's life? Music, the funkier the better. And she doesn't just listen, she also plays, DJ's, and has pipes that would make most opera singers sick.
- Beta Bitch
- Beta Couple: With Sheen.
- Black Best Friend
- The Chick
- Fartillery: Gets this when she ate the Belch Boy packet in "The League of Villains" and proves to be better at it than Carl, given that she doesn't need seltzer or to be shaken to burp, and she can eventually control her burping to do it at will.
- Gasshole: Becomes one after eating the Belch Boy packet in "The League of Villains", even to the point of making a dance out of her burps.
- Give Geeks a Chance
- Important Haircut: Libby gets one in the Beach Party Mummy episode to fool a bunch of mummies that were chasing the gang. She keeps the new look for the remainder of the series.
- Incredibly Long Note: Turns this into a Chekhov's Gun in "The Great Egg Heist."
- Only Sane Woman: Grows into this more and more as the series went on. By the end she's the most levelheaded character in the gang, much to her occasional frustration.
- Promoted To Opening Credits
- Puppy Love: With Sheen.
- Sassy Black Woman
- Satellite Character: Was originally one for Cindy, and several of her earliest appearances had her personality as more or less an echo of Cindy's, but as the characters got more development, she became more distinct.
- Shipper on Deck: She's FOREVER pleading with Cindy to just tell Jimmy how she feels and get it over with!
- Token Minority
- Tomboy: She adjusts really quickly to becoming "Burp Girl" in "The League of Villains", even proving better at using the sonic-blast burps than Carl did in "The N-Men".
- Women Are Wiser
- Youthful Freckles: Libby gained some in season 2 after her redesign.
Voiced by: Frank WelkerJimmy's robotic dog.
- Do-Anything Robot: He does eleven billion and four things! Except clean up after himself.
- Non-Human Sidekick
- Robot Buddy
- Robot Dog
- The Speechless
- Team Pet
Hubert "Hugh" Beaumont Neutron
Voiced by: Mark DeCarloJimmy's father. Averts Father Knows Best. Nevertheless, he's a chipper, upbeat family man who always has time to dispense words of wisdom for Jimmy, even if most of the time those words are better left ignored. Has an obsession with ducks.
- Adults Are Useless
- Bumbling Dad
- Cloudcuckoolander: Quite possibly the largest one in the series.
- The Ditz
- Gasshole: Even without drinking the Burping Soda, Hugh has burped more than anyone else in the series, including Carl.
- Idiot Ball: Holds it consistently, like it's his firstborn child.
- "Jump Off a Bridge" Rebuttal: Twisted.Jimmy: "Aw, but Dad! All my friends are going!"Hugh: "Now, Son, if all your friends were named Cliff, would you jump off them?"
- Obliquely Obfuscated Occupation: Averted. He's a car salesman.
- Trademark Favorite Food: Pie.
- Ugly Guy, Hot Wife: With Judy.
Judith "Judy" Neutron
Voiced by: Megan CavanaghJimmy's mother. She's happy to cook and clean and run the household but does want some appreciation for all she does. After all without her, Jimmy and Hugh's lives fall to pieces.
- Action Mom
- Adults Are Useless: Subverted. She's incredibly athletic, coordinated, intelligent, and she keeps a plasma rifle in her utility closet (for those tough ground-in stains!)
- Beauty Mark
- Ditzy Genius: Not ditz per se (she's certainly the intelligent one in her marriage with Hugh and more rational than he is) but she has her moments of ditziness. There are also numerous moments where she demonstrates it's definitely from her side of the gene pool that Jimmy gained his intellect.
- Full Name Ultimatum: "James Issac Neutron!"
- Gasshole: Becomes this after chugging some of Jimmy's Burping Soda.
- Hypnotize the Princess: Ever noticed she gets hypnotized quite a bit on this show?
- Mama Bear: "Get away from my family, you ugly bucket of bolts!"
- Mundane Utility: Use a demolecular cannon beam to clean difficult stains.
- Only Sane Woman
- Stacy's Mom
- Ugly Guy, Hot Wife: With Hugh.
- Women Are Wiser
Voiced by: Candi MiloThe "cool guy" that everybody loves at school, especially the girls.
- All Girls Want Bad Boys
- Bad Butt: Before his later characterization took hold.
- Cross Dressing Voice
- Demoted to Extra: Earlier episodes were building him up to be an important character. Then he vanished.
- He even got his own toy in the Wendy's Kid's Meals when the original film came out.
- Flanderization: In the movie, Jimmy takes backseat as Nick leads the charge against the Yolkians, and the class Bad Butt even manages to take out a couple of Yolkian guards by hijacking one of their spears... only to lose momentum upon seeing the giant alien-chicken, at which point he becomes completely useless and Jimmy has to lead the charge himself. Nick's later Paper Tiger characterization suggests he would balk at even taking on the guards, if he had to do it again.
- Paper Tiger: He's the ultimate cool dude, the girls all dig him, and he's supposed to be tough. In the movie, his part of the plan is to take care of the Big Bad while the others rescue their parents. One look at his competition, though, and he goes screaming like a little girl.
- And it only goes downhill from there…
- Screams Like a Little Girl
Voiced by: Phil La Marr
- Cloudcuckoolander: He makes Sheen look sane by comparison.
- Dance Sensation: The "Slap Dance" from his homeland. "Slap slap slap! Clap clap clap! Slap slap slap! Clap clap clap!"
- Funny Foreigner: Kind of like Fez or Rolf. The difference is that Bolbi's country is actually named (Backhairistan).
- Hidden Depths: He's a very good actor.
- Strong Family Resemblance: His sister is just a slightly shorter version of him in blonde braids.
- The Sixth Ranger: Starts taking a role similar to this in later episodes.
- Trademark Favorite Food: Kebabs. They appear to be standard cuisine in his country.
Voiced by: Kath SoucieThe girl of Jimmy's dreams, and sometimes the motivation for hi jinks in his effort to impress. Cindy doesn't care for her... for some reason.
- Bare Your Midriff: When she played Lady Macbeth.
- Betty and Veronica: Quite literally the sweet natured Betty to Cindy's Veronica.
- Beauty Mark
- Shallow Love Interest: For the most part. She doesn't get any true focus outside of Jimmy's love glazed POV. Finally subverted a bit when we see, that despite her pleasant demeanor, she does have her limits. And no, she's not oblivious to Jimmy's crush on her (she'd have to be deaf, dumb, and blind, actually), or Cindy's crush on Jimmy for that matter. She lets Cindy have him.
- Berserk Button: MUSIC. Seems to have stopped after their first appearance, though, as one can be seen during a big musical number at one point.
- Fish Eyes
- Killer Rabbit
- Villain Decay: After their first appearance, Twonkies are treated as if they were normal rabbits.
- Monster of the Week —> Recurring Extra
SamOwner of the local hangout joint, The Candy Bar.
- Bullying a Dragon: Does so in the superhero episode the N-Men. Jimmy is a rampaging orange monster but upon seeing his parents, he starts calming down. Until Sam decides to throw fruit in Hulk/Jimmy's face. Needless to say, the mutated Jimmy doesn't take too kindly to it.
- Jerkass: N-Men episode again. Granted something should have been done to try to help the kids control their new found powers. However, calling the military up to imprison them and then telling the kid's parents they were just freaks?
- Verbal Tic: Has a habit of ending his sentences with, "Yeah!".
Voiced by: Patrick Stewart (movie), S. Scott Bullock (TV series)King of the Yolkians, and Jimmy Neutron's archenemy.
Voiced by: Tim CurryJimmy's arch-nemesis and the show's most recurring antagonist.
- Absent-Minded Professor: Calamitous when introduced was never able to finish anything, even his own sentences. From his second appearance onwards, he can now talk in complete sentences thanks to self-help classes.
- Big Bad: Expect him to fall into this role a lot, especially during crossovers.
- Evil Laugh
- In Their Own Image: After being fused with von Strangle, he intended to recreate all reality as he saw fit.
- Mad Scientist
- Mini-Mecha: A humanoid red model was his best work in his debut. The only thing he hadn't finished was putting in a bathroom.
- Would Hurt a Child
Voiced by: Wendie MalickProfessor Calamitous's daughter. Jimmy, Carl, and Sheen are easily seduced by her looks.
- Beauty Mark
- Beleaguered Assistant
- Deadpan Snarker
- Dude Magnet: How every guy in the show reacts towards her.
- Impossible Hourglass Figure
- Interspecies Romance: With Junkman due to Jimmy's Love Potion.
- Mad Scientist's Beautiful Daughter
- Meaningful Name
- Ms. Fanservice
- Running Gag: Every time she mentions she wanted to have a certain career other then villainy, she always gets interrupted or cut off. It was to make aglets for a living.
- Then Let Me Be Evil: Apparently she never wanted to be evil; just felt obligated to because her father was doing it.
- The Ugly Guy's Hot Daughter
- Ugly Guy, Hot Wife: With Junkman.
- Woman in Black
Voiced by: Tim AllenThe host of the hit game show "Intergalactic Showdown" and the main villain of the TV movie "Win Lose and Kaboom".
- Big Bad: Of "Win Lose And Kaboom".
- Doing In the Wizard: His seemingly supernatural hold over reality, time and space is actually caused by a pair of matrix generators hidden in his cuff links.
- Faux Affably Evil: Rarely drops his cheery, hammy attitude even while threatening to blow up people's planets. At the end, he finally stops and decides to get serious.
- Hypocrite: Insists during the race that there's no cheating allowed, but permits the Brains to put Jimmy and the gang into a Lotus-Eater Machine. Later he panics at the idea of his quadrant being blown up despite the fact that his entire show is about blowing up completely innocent planets simply because their species lost a game.
- Karma Houdini: The worst he gets is being forced to hand over his show to the Brain aliens and advertise an exercise machine that implements Electric Torture. Probably justified as he's implied to be indestructible.
- Large Ham: He's a Game Show host. It comes with the territory.
- Omnicidal Maniac: "Winner gets a brand new car! Loser gets their home planet destroyed!"
- The Omnipotent/Reality Warper: Thanks to the matrix generators in his cuff links.
- Smug Snake
- Time Abyss: Implied, as April states that his show has existed for eons.
- Villainous Breakdown: Loses it when he discovers that his show is about to be destroyed.