The Jimmy Timmy Power Hours are a trilogy of hour-length specials produced for and aired on Nickelodeon in 2004 and 2006. As suggested by the title, they are a series of Crossovers between two of the network's most popular cartoons, The Adventures of Jimmy Neutron, Boy Genius and The Fairly OddParents!.

It all starts in the first special, when Timmy, in need of a good science project, wishes to go to "the greatest lab in the universe", and Cosmo and Wanda transport him to Jimmy's not-so-secret lab. An accidental meeting between the two results in Jimmy getting transported to Timmy's world, where he mistakenly believes Cosmo and Wanda are some kind of advanced holographic computer programs (because he thinks Timmy is also a genius and is also too scientific minded to believe magic is real), and Mr. Crocker steals his transportation device, which he then uses to take over Fairy World. Back in Retroville, Timmy develops mutual affections for Cindy Vortex and accidentally turns Goddard into a killer robot based on "Decimator", his favorite video game. The boys eventually manage to solve their respective problems and return to their own worlds, and all ends well...

...Until two years later, when the second installment, When Nerds Collide!, came out. Timmy is looking for a date for the Friday the 13th school dance, and since Trixie Tang isn't around for him to unsuccessfully ask out, he goes to Retroville again, this time taking Cosmo and Wanda with him, so he can get Cindy to go out with him. However, Jimmy wants to ask out Cindy as well, which soon leads to an all-out brawl between the two as Cindy is torn between which boy she should go with. This naturally does not sit well with Jimmy. As if that weren't enough, Professor Calamitous is on the loose again, and so are the Anti-Fairies.

Finally, in the third special, The Jerkinators!, Timmy and Jimmy put aside their differences and start hanging out together. They grow bored with their outmatched villains and create a new villain to fight. But things take a turn for the worse when this new villain, named Shirley, steals Cosmo and Wanda's magic powers and Jimmy's intelligence!

Outside of these specials, Jimmy and Timmy would join forces a few more times in the Nicktoons Unite! video games. See also Rugrats Go Wild! for another Nicktoon crossover.

The Jimmy Timmy Power Hour provides examples of:

• Accidental Misnaming: In "The Jerkinators!", Timmy, observing Jimmy working on their villain, calls Cindy "Debbie" as she enters the lab and tries to flirt with them.
• Accidental Tickle Torture: Two instances occur in The Jerkinators!, both involving Jimmy (and later, Timmy) pulling a golf club out of Cosmo in the form of a golf bag, which prompts this reaction from him.
• Adaptive Ability: Shirley, the villain Timmy and Jimmy create, has this power, due to a typo Timmy made.
• Affably Evil: Even after Shirley learns that Jimmy and Timmy abandoned him, he’s nothing short of friendly to them and their friends. Especially evident when he grabs things from each of their universes and creates voids that would destroy them in two days. He’s decent enough to give them a warning ahead of time and gives them a portal to his universe to hang out with him.
  Shirley: I don’t care if your universes are falling apart. It’s you guys I care about!
• Agent Scully: Being a boy of science, Jimmy refuses to believe the existence of fairies and thinks that Cosmo, Wanda, and everything in Fairy World are high tech holograms or reality bending programs, even after seeing what they can do is beyond science. Cosmo and Wanda roll with this fact so Jimmy does not find out the truth so they don't have to go away forever
• Ain't Too Proud to Beg: In the first special, after Crocker takes over Fairy World and Jimmy is about to leave the powerless fairies behind (believing them to be computer holograms), Cosmo frantically tells him he can't leave them.
• And I'm the Queen of Sheba:
  Jimmy: I'm not Timmy, I'm Jimmy. Jimmy Neutron.
  Sanjay: And I am not Sanjay, I am Yogi Bear, and I am smarter than the average bear.
• Angry Guard Dog: In the first special, when Crocker takes over Fairy World, he turns Jorgen into a Schnauzer. This comes to bite the former back literally after Jimmy defeats him and the still transformed Jorgen attacks Crocker, which traumatizes the latter to the point he forgets all about Fairy World.
• And You Thought It Was a Game: In the first special, when Crocker takes over Fairy World, Jimmy was initially willing to leave the depowered fairies to their fate to teleport back to Retroville, believing them to be mere holograms and that Fairy World was only a simulation. However, upon hearing Timmy saying they're real and seeing them scared, he realizes they must be more than holograms and decides to save them by defeating Crocker and fixing the big wand.
• Apple of Discord: Cindy tries to be this in the third special when Jimmy and Timmy are seemingly neglecting their other friends in favor of each other, banking on their mutual crush of her to break them apart. It doesn't work.
• Armor-Piercing Response: In the first special, Jimmy calls out to Timmy as to why does he care so much about his fairies, whom to Jimmy are nothing more than computer programs and thus not real. Timmy responded back by reminding him that he cares for Goddard like a real dog, which is enough to convince Jimmy to protect Fairy World from Crocker.
• Art-ernate Universe: The crossover plays this up for all its worth, displaying the characters of both The Fairly OddParents! and The Adventures of Jimmy Neutron, Boy Genius in each other's art style when they go into each other's universe.
  Timmy: Hey, why is everything so bulgy?
• A Taste of His Own Medicine: In the first special, Crocker steals Fairy weapons and uses them to de-power Fairy World and turn Jorgen into a dog and two fairy guards into animals. After Jimmy restores magic on Fairy World, one of the first things he does is to use Jorgen's wand to turn Crocker into several lab objects until the latter surrenders.
• The B Grade: Crocker, mistaking Jimmy for Timmy, gives him an F, which burns his hand.
• Bait-and-Switch Time Skip: In the third Power Hour, Timmy and Jimmy program their own villain, but when he becomes clingy, they take a break and tell him to meet them at the mall in an hour. The villain waits as the sky cycles through day, night, and various forms of weather, and believes he has been abandoned, becoming angry. The next scene shows Jimmy and Timmy programming a new villain in their treehouse, but it's revealed that they didn't abandon their old villain for that long:
  Cosmo: Wow! I can't believe the sun came up, went down, came back up, and then we had rain and snow and night again all in one hour!
• Because You Were Nice to Me: Cindy's crush on Timmy stems from how he thinks she's smart, appreciating her advice and asking if she wants to help him with his science project, unlike Jimmy who is much ruder to her.
• Berserk Button: In the first special, when Jimmy fights against a powered Crocker, the latter (still believing Jimmy to be Timmy) says once the fight is over, he will still give the former an F, this angers Jimmy.
  Mr. Crocker: I'm going to give you an F... minus!
  Jimmy: No one gives Jimmy Neutron an F!
• Big Bad: Crocker and a Brainwashed and Crazy Goddard in the first, Anti-Cosmo then Professor Calamitous in the second, and Shirley in the third.
• Big "NO!": Happens twice in the first two specials.
  • In the first one, Timmy lets out one when he sees Mr. Crocker had gotten to Fairy World.
  • The second one has Jimmy scream out, combined with Eat the Camera after realizing that Timmy's going to ask Cindy out to his Friday the 13th dance, when he was going to do it himself.
• Bond One-Liner: Decimator Goddard in the first special shouts out one whenever he "defeats" a "player":
  Decimator: Player (number), DECIMATED!
• Breaking the Fourth Wall: Everyone points out the fact that The Fairly OddParents! world is 2D and Jimmy Neutron is in CGI.
  • During the climax of the first special, Jimmy states to the audience that he totally knew that the reason that the Big Wand wasn't turning back on was because it wasn't plugged in.
• Brick Joke: One that comes to fruition in the second movie; In an earlier Jimmy Neutron episode involving Carl's dreams, we learned that he's married to a turkey in his dream canon. In "When Nerds Collide", they have to make Jorgen Von Strangle angry and choose to do this by violating Da Rules. The first thing they do? Make Carl pretend to fall in love with a turkey.
• Call-Back: There are quite a few running gags that persist across all the specials, and a few punchlines that are set up in previous ones. For example:
  • Timmy's "you guys are totally cramping my style! Which I apparently have in this universe!" to Jimmy's friends from the first special becomes "you guys are totally cramping my style! Which I now have in my own universe with this one girl!" when Timmy brings Cindy to Dimmsdale and Jimmy's friends follow.
  • It's a running gag in the first special that whenever Timmy wants to avoid the consequences of something, he puts on a cheap disguise and pretends to be someone else, explaining why everyone in Dimmsdale thinks Jimmy is actually Timmy. When Jimmy tries to find Timmy in Dimmsdale in the second special, he briefly gets sidetracked because - again - Timmy's parents still think he's Timmy for the same reason.
• Cassandra Truth: In the first special, as a Running Gag when Jimmy and Timmy switch universes, everyone in Retroville thinks Timmy is Jimmy in disguise, while everyone in Dimmsdale think Jimmy is Timmy in disguise. But no matter how many times the boys correct them, they don't believe them (much to their annoyance). Only Cosmo, Wanda, Cindy, and Libby immediately realize the truth, and Carl and Sheen find out when they see the real Jimmy on Goddard's screen.
• Cock-a-Doodle Dawn: In the second special, a rooster is about to crow as the sun came up, only for the sun to go back down thanks to the Anti-Fairies stopping the earth's rotation. Once Jimmy, Timmy, and the others draw all of them in and cause the earth to start spinning again, the sun comes up and the rooster is joyfully able to crow.
• Comical Overreacting: Sheen, when he realizes that Timmy is not "Small-headed Jimmy" like he assumed: "EVERYTHING I KNOW IS A LIE!!" Even funnier since this is the last thing he says in the first special.
• Conscience Makes You Go Back: During the climax of the first special, Jimmy's only concern is getting the Auto-Poofer from Crocker so he can go back home. He is fully prepared to leave Cosmo, Wanda, and all the other fairies to their fate since he thinks they're all just digital. But when Timmy tells him that they're as real to him as Goddard is to Jimmy, Jimmy reconsiders and decides to stop Crocker.
• Continuity Cavalcade: In the third special, the villain collects people and objects from both worlds and mashes them into one universe. The results in several scenes of him lording over the combined worlds, which are full of continuity nods and references to both series - including dozens of background characters from Jimmy Neutron redesigned in The Fairly Oddparents' style.
• Continuity Nod:
  • Jimmy mentions in When Nerds Collide! that Professor Calamitous must have escaped the time of dinosaurs, where he was left with several other Jimmy Neutron villains in "League of Villains". Also, his original partner is Dr. Moist, a one-off villain from "The Evil Beneath".
  • In the first special, Cosmo and Wanda introduce themselves to Jimmy the same way they did to Timmy in the Fairly OddParents pilot.
  • At the beginning of When Nerds Collide, Anti-Cosmo is a wanted fugitive having escaped from captivity in "The Gland Plan".
• Contrasting Sequel Antagonist: As the fairy-hunting Crocker was the antagonist of the first Power Hour and the mischievous Anti-Cosmo and underaccomplished mad scientist Professor Calamitous were the antagonists of "When Nerds Collide!", the antagonist of "The Jerkinators!", Shirley, is a standout from all the rest. He's a being brought to life by Jimmy and Timmy so they could have a new villain to fight. Unlike the devious villains from the last two Power Hours, Shirley has more sincere and considerate traits than the last two while he becomes furious from the deception of the boys to the point where he becomes the villain they wanted him to be. Fortunately, after the two apologize to him for treating him poorly, he stops harming their worlds and takes up a more friendly position.
• Create Your Own Villain: In the third crossover, after defeating all their other rogues easily, Jimmy and Timmy decide to do this quite literally, resulting in Shirley. Unfortunately, it becomes a case of Gone Horribly Right quite literally.
• Crippling Overspecialization: In the first crossover, upon learning that Timmy's Auto-Poofer can only teleport the user to Timmy's room, Jimmy considers it "limited" and modifies it into a universal teleporter. Unfortunately, Crocker uses it to get to Fairy World.
• Crossover: Between The Adventures of Jimmy Neutron, Boy Genius and The Fairly OddParents!.
• Crossover Combo Villain: Jorgen Von Strangle and Professor Calamitous end up getting fused together in the second crossover.
• Crossover-Exclusive Villain: Shirley, the Big Bad of the third crossover, is unique to the special.
• Crossover Foil: Timmy Turner is a Book Dumb average kid with magical fairy godparents, while Jimmy Neutron is a Child Prodigy inventor who has Scully Syndrome when faced with any proof that magic exists. In spite of their differences, they are both well-meaning troublemakers who love a good time, which helps them to become best friends across dimensions. They are also both attracted to Cindy, which causes some issues in the When Nerds Collide special.
• The Cuckoolander Was Right: Cosmo was the first character alongside Wanda to immediately realize Jimmy Neutron is not Timmy in disguise.
  Cosmo: Oh, no, that kid isn't Timmy! His swirly, fudgey hair is way too perfect!
  Wanda: Worse, if he finds out that we're Timmy's fairies, we'll have to go away forever!
• Curb-Stomp Battle: Jimmy and Timmy's team up in the third one turns their encounters with their individual villains into this.
• Dance Party Ending: When Nerds Collide ends with everyone enjoying the Friday the 13th dance and Jimmy and Timmy having Cindy as both their dates.
• Deadly Euphemism:
  • Jimmy unintentionally invokes this trope when asking what damage Crocker would do to Timmy's "computer simulation" in the first special:
    Cosmo: Wait, fudge-head, you can't leave us! Crocker's going to—
    Jimmy: Zap the memory? Wipe the C drive?
  • "Timmy, you have to stop him! He's going to let Crocker wipe our C drive, whatever that means, and I like to wipe my own stuff!"
• Delayed Reaction: In the first special when Jimmy sees Cosmo and Wanda and assume they're holograms, he thinks they might be imperfect prototypes, to which Cosmo replies that Wanda might not perfect but she's the one who agreed to marry him, which touches her for a moment upon she realizes what he said.
  Jimmy: That's probably why you're imperfect prototypes.
  Cosmo: Well, she might not be perfect, but she's the one who said yes.
  Wanda: Aw... (realizes what he meant) Hey!
• Denser and Wackier: Compared to Jimmy Neutron, since the crossovers generally use humor more like The Fairly OddParents! — resulting in the Jimmy Neutron characters acting even sillier than usual and getting into screwier situations — as well as much more slapstick. This happens especially when the characters are actually in Dimmsdale (which compared to Retroville is practically Cloudcuckooland).
• Diegetic Soundtrack Usage: One for The Fairly OddParents in the third special. Jimmy also drops the same quip in the first special.
  Shirley: And once I take away your wands, Timmy will be just an average kid who no-one understands.
  Cosmo: Someone should write a song about that!
• Disc-One Final Boss: Anti-Cosmo in the second one. After his defeat, Professor Calamitous takes over.
• Disney Death: Jimmy and Timmy suffer this in "When Nerds Collide" when they are blasted by a Calamitous controlled Jorgen, they are out of action several minutes until it revealed they just were turned into snails.
• Dissonant Serenity: In the first crossover, the fairy tour guide describes in the most casual tone the violent way Crocker is being mauled by Jorgen.
• Engineered Heroics: In the first special, Cindy believes that Timmy created the crisis and acted like he didn't know what he was doing just so she could solve it, and thinks that's very sweet. Actually though Timmy really was that clueless.
• Everybody Cries: In When Nerds Collide, Cosmo, Wanda, Carl, Sheen, and Libby cry when it looks like Timmy and Jimmy have been vaporized by Jorgen.
• "Eureka!" Moment: In the first special, Cindy tries to get Timmy to do one of Jimmy's Brain Blasts. Timmy tries...and fails. He then simply states that if he can't defeat a difficult level, he'll just Rage Quit and pull the game out of the console which Cindy states is still a good idea.
• Exact Words: Jorgen told Anti-Cosmo nobody in their universe would be able to free the Anti-Fairies. Anti-Cosmo then looked for somebody from another universe.
• Extremely Short Timespan: When Nerds Collide is set entirely on Friday the 13th, with 80% of it taking place in the morning with the world saved some time in the afternoon, and the final scene is set that evening at the dance.
• Eye Color Change: For some reason, Cindy and Sheen’s eyes turn blue when in Timmy's world.
• Faked Rip Van Winkle: In the third crossover, AJ attempts to cryogenicly freeze himself for 1,000 years. However, a second afterwards, Chester comes and wakes him up, leading AJ to believe he's in the future for the majority of the special, causing him to take the situation with Shirley in stride. During the climax, when he's finally told he's still in the present and the crisis is happening now, he has a Freak Out.
• Failed a Spot Check:
  • In the first special after Jimmy accidentally teleports to Dimmsdale with Timmy's Auto-Poofer, Timmy somehow grabs one of Jimmy's mini lasers and mistakes it for such despite the fact it looks nothing like it. It takes Cindy tapping into the laser for him to realize the truth.
  • In the third special, neither Jimmy, Cosmo, nor Wanda seem to notice that Timmy typed "Adaptable" instead of the intended "Adoptable" until it was too late.
• Fluffy the Terrible: Shirley in The Jerkinators. Subverted when he refers himself as "The villain whose name is not Shirley."
• Four-Fingered Hands: The Fairly OddParents characters get an extra finger on each hand in Jimmy's world, while the Jimmy Neutron characters lose a finger in Timmy's world.
• Funny Background Event: When Cindy is ranting to Libby about Jimmy not asking her to the dance, Libby says that it's not like a date will fall through the ceiling. Cue Timmy falling through the ceiling. In the following scene, you can see Libby shaking a finger at the ceiling trying to summon things.
• Gender Bender: The ending of When Nerds Collide has Carl getting Cosmo and Wanda to turn a shrunken Calamitous into a copy of Jimmy's mom. Calamitous is appropriately horrified.
• Gratuitous Spanish: It happened twice in the trilogy. In JTPH1, using Timmy's Auto-Poofer, Jimmy tries to go to Retroville, and walked as far as Mexico just so he could try getting somewhere else with the Auto-Poofer, even saying "Jivamé à Retroville!" which is "To Retroville!" in Spanish, but still ends up in Timmy's house at Dimmsdale since the Auto-Poofer was actually meant to teleport the user there. JTPH2 features this scene:
  Cosmo: Ah! They DO speak Spanish here!
  Wanda: Silencio, eh stupido!
• Hypno Fool: Judy is hypnotized into thinking she's Mighty Mom in the first special. The special never shows her getting unhypnotized.
• Hope Spot: Just as Jimmy manages to combine Timmy's Auto-Poofer with his Game Buddy to turn it into an actual teleportation device to take him to Retroville, Crocker barges in takes the device for himself and uses it to transport him to Fairy World.
• Hypocritical Humor: "How does he do it, magic?".
• If You Ever Do Anything to Hurt Her...: A platonic example. At the second special, when Timmy loans Cosmo and Wanda to Carl, Sheen and Libby to keep them occupied while he asks Cindy out, Libby agrees but threatens to beat Timmy up if he breaks Cindy's heart.
  Libby: Alright. (grabs Timmy) But if Neutron was right and you break Cindy's heart, reality isn't all that's gonna get bent around here. Get it?
  Timmy: Got it!
• I'm Standing Right Here: During the climax of the first special, Jimmy asks Timmy why he cares so much about his faries, since he thinks they're just holograms and Fairy World is a big computer simulation and are thus "not real". After saying this, Goddard comes into view whimpering in response to this. Timmy then claims that even though Goddard is computerized Jimmy treats him like a real dog, and Cosmo and Wanda mean just as much to him as Goddard does to Jimmy.
• Informed Kindness: The reason Shirley spares Cindy, Libby, Carl, Sheen, Chester, and AJ is supposedly because they were nice to him. Thing is, all six of them have barely interacted with him prior to him making this declaration. AJ fawns over him as "the future of mall security", and Cindy (correctly) warns him that Timmy and Jimmy would abandon him, but that's about it... and even in the latter instance, she wasn't exactly gentle about it, being Cindy.
• In Harm's Way: The main conflict in The Jerkinators happens when Timmy and Jimmy decide to create their own strongest villain, as they don't have any nemeses that can seriously challenge them. To put it briefly, it works better than they expected.
• Instantly Proven Wrong: At the first special, when Crocker steals the teleportation pen from Jimmy and states that he will use its magic, Jimmy calls him crazy and tells him that magic doesn't exist, but Crocker quickly proves him wrong by teleporting himself, Jimmy, Cosmo and Wanda to Fairy World, albeit Jimmy still believes it to be an holographic fairy video game.
• Internal Reveal: After Retroville is saved and Goddard returns to normal, Jimmy appears on his screen; this in turn causes Carl and Sheen to realize Timmy is not Jimmy in disguise as they thought.
  Timmy: Hey, it's that kid!
  Cindy: It's Neutron!
  Sheen: (looks back and forth at Timmy and the real Jimmy onscreen) But I thought that...?
  Carl: Then you're not...?
  Sheen: EVERYTHING I KNOW IS A LIE!!!
• It Began with a Twist of Fate: The first special owes its existence to Timmy's Auto-Poofer.
• Joke and Receive: In the second special, when Cindy complains about not having a date, this happens.
  Libby: You think a date's just gonna come crashing through the ceiling? (points upward as she says this)
  Timmy: (falls through the ceiling on cue) Hi! Remember me?
  Libby: (holding up her pointer finger in amazement) I must use this power for good!
• Invisible to Normals: Averted in the second special regarding the Anti-Fairies, as after Anti-Cosmo escapes, Jorgen changes Da Rules so Anti-fairies could be visible on Earth and as seen in subsequents seasons, it sticks.
• Lack of Empathy:
  • Jimmy is content on leaving Fairy World to be conquered by Crocker since he believes the fairies are computer programs and thus not real. It takes Timmy to remind Jimmy of his relationship with Goddard to save Fairy World.
  • Timmy callously treated Retroville as his personal playground, hypnotizing Jimmy's mom to get her off his back and leaving his dad to possibly die at Decimator Goddard's hands, as well as mutating random wildlife with Jimmy's inventions. Sheen expresses awe at his "complete disregard for the lives of himself and those around him".
• Laser-Guided Amnesia: In the first special, after Crocker is defeated by Jimmy, Jorgen, who was turned into a schnauzer by Crocker earlier, declares he will rip Crocker's memory to bits with his muscular canine teeth and violently attacks Crocker, destroying his memory of Fairy World (as well as rearranging his internal organs). Crocker is last seen in the special heavily bandaged, not only having lost his memory, but also left traumatized of schnauzers.
• Leaning on the Fourth Wall:
  • In the first Power Hour, Timmy notices how everything's so "bulgy", in the computer-animated Jimmy Neutron universe, while Jimmy notices his depth is gone when in the hand-drawn Fairly OddParents universe.
  • When Jimmy and the gang arrive in the FOP universe in "When Nerds Collide", Sheen finds that he's flat in Timmy's universe.
  • "The Jerkinators!", Sheen, perplexed by Jimmy and Timmy becoming friends, he looks into the view of the camera and asks what that means, only to cut to Libby in front of him. This happens twice when Cindy returns.
  Sheen: Do you know what this means? Do you? Do you?
  [Cut to Libby again.]
  Libby: Seriously? You've got to stop doin' that.
• Love Triangle: Jimmy/Cindy/Timmy.
  • Cindy falls for Timmy in the first special (albeit thinking he's smarter than he is), which sets off Jimmy due to his own crush.
  • In the second special, they're both competing to take her to their respective dance, and Cindy learns Timmy isn't a genius but is still fond of him enough to wish to go to both dances (Jorgen makes it happen).
  • In the third, Jimmy sees Timmy planning to come hang out with Cindy through his portal and once again gets angry, leading to the two of them racing to go see her. Cindy later tries to exploit this when it looks like Jimmy and Timmy are getting too chummy and neglecting their other friends by being the Apple of Discord, but she just gets ignored herself.
• Magic Versus Science: Most evident in the second special. In fact, it sort of comes off as Timmy cheating, as everything Jimmy makes is derived from his understanding of the universe, while Timmy can wish almost anything into existence.
• The Man Behind the Curtain: Parodied by Cosmo and Wanda when it was revealed they were the ones operating the mecha and the "Jimmy" piloting it is a lookalike dummy while the real Jimmy repairs the Big Wand:
  Cosmo: Pay no attention to the fairies operating the fudge head suit!
• Medium Blending: Depending on which world the characters are in, they are either hand-drawn or CGI.
• Mistaken Identity: In the first special, almost evryone Timmy and Jimmy meet in each others world mistakes them for the other. Only Wanda and Cosmo realize that Jimmy isn't Timmy. Though Cindy and Libby immediately realizes that Timmy isn't Jimmy either, Cindy mistakenly believes he's a genius friend of his, who is much nicer than he is.
• Morality Pet: A literal example. In the first special, when Jimmy is initially willing to leave the fairies at Crocker's mercy believing them to be holograms, he asks Timmy why he cares for them so much, then Goddard appears next to Timmy, and the latter comments that Goddard is computerized and still Jimmy cares for him as Timmy cares for his fairies. This is what convinces Jimmy to stop Crocker and save the Fairy World.
• Mundane Solution: After fixing both universes and Jimmy is trying to come up with an invention to get home, Timmy decides to fix that and simply wishes he and Jimmy were back in their own hometowns.
  Cindy: (giggles) He's so smart!
• Never Say "Die": In the second special, Jimmy pretends to kill Timmy by "wishing" that "Timmy Turner was gone."
• Nice Job Breaking It, Hero!: Pretty much the case in all three movies due to both Jimmy and Timmy:
  • JTPH1 — Timmy was the one who caused both him and Jimmy to be stuck in each other's universe. While at Retroville, Timmy ends up turning Goddard into a giant Killer Robot that nearly destroy the city. Meanwhile, Jimmy's attempt to return to his universe ends up bringing Crocker to Fairy World, which an annoyed Cosmo lampshades to Jimmy.
  • JTPH2 — The boys' fight for Cindy's affection first made Calamitous to discover the existence of fairies and to form a partnership with Anti-Cosmo to release the other Anti-Fairies (which Anti-Cosmo mockingly points out to both boys) and later, Timmy's attempt to use one of AJ's devices causes Calamitous to genetically fuse with Jorgen, who nearly destroys Jimmy's universe.
  • JTPH3 — The boys' create a new villain for them to defeat but because of Timmy's negligence, he ends up giving the villain adaptive ability which causes all their efforts to defeat him to fail and he nearly destroys both universes.
• Nobody's That Dumb: When he first meets Jimmy, Cosmo immediately knows that he is not Timmy. The other citizens of Dimmsdale however think he is Timmy wearing a disguise.
• Now That's Using Your Teeth!: When Timmy is trying to shut down Goddard when he's corrupted by his Decimator game, his mini-laser pen runs out of power as he is trying to get into the terminal. Sheen tells for him to use his giant teeth instead, and Timmy successfully bites the box open and spits out the lock.
• Omnicidal Maniac:
  • Professor Calamitous tries to blow up his own universe in the second part of the trilogy using Jorgen's magic while temporarily fused with him.
  • Shirley creates expanding red vacuums that would have destroyed both universes in the third part of the trilogy.
• Only Sane Man: In the first special, Cosmo and Wanda were the only ones who knew at first glance Jimmy was not Timmy in disguise. On a similar note, Libby realized right away Timmy was not Jimmy.
• Opening Shout-Out: In "Jerkinators", Shirley makes a reference to The Fairly OddParents intro some point into the special.
  Shirley: You guys think you're so special, but you'll just be average kids that no one understands!
  Cosmo: Someone should write a song about that!
• Out-of-Character Moment: Cindy acts unrealistic, oblivious and gullible in the trilogy and makes stupid assumptions in the first one. Libby lampshades this.
  Libby: Jimmy's gone, New Jimmy [Timmy]'s useless and Cindy's acting like a complete dork. I mean, what's up with that?
• Paper-Thin Disguise: Discussed, as Timmy has apparently done this to try and get out of science fairs often enough (with "Kent Quasar" and "Buzz Atoms" getting brought up) to the point everyone thinks Jimmy Neutron is just one of many for Timmy. As we know, this obviously isn’t the case.
• Plot Hole:
  • In the first Power Hour where Jimmy asks for Cosmo and Wanda's help to get back to Retroville and bring Timmy back to Dimmsdale, Wanda states they can't do it unless Timmy wishes for it, which is contradicted by their teleporting to Hawaii with their own free will after they sent Timmy to Retroville.
  • In the beginning of When Nerds Collide!, Jorgen changed Da Rules so that Anti-Fairies can be seen on Earth by humans, which makes no sense since Jorgen is a follower of Da Rules like every other fairy and is forbidden from changing them.
• Reactive Continuous Scream: Parodied. When Cosmo and Wanda scream at the sight of Jimmy, he deliberately, consciously decides to scream back. Why exactly?
  Jimmy: I'm not familiar with how you greet people in this dimension, but okay... (Jimmy shrugs before screaming at the fairies, who scream again. Cue an exhange of a couple more screams.)
• Running Gag: In the second special, Timmy running behind trees to "invent" stuff.
  • Also, Cindy grabbing Timmy's lips before he has a chance to wish for something.
• Sarcasm Mode: In the second special, when Anti-Cosmo is about to be sucked by Jimmy's Hypercube, an amused Timmy sarcastically comments that it looks like Anti-Cosmo is the one with bad luck now.
• Seasonal Baggage: As Shirley waits at the mall, the sun "came up, went down, came back up, then had rain and snow and night again", all in one hour.
• Secret Diary: In the second special, Cindy is shown to have a secret diary, which Timmy uses to impress her by taking her on a ride on Cosmo and Wanda transformed into winged unicorns, with Cindy having the pink dress she always wanted with matching tiara and shoes and comments that it's like someone read her secret diary and saw her secret wishes while Timmy secretly holds Cindy's diary, which he soon wishes back to its proper place before Cindy could notice it.
• Security Cling: When A.J. finds out from Libby he never froze himself into the future and everything is happening right now, he grabs onto Libby and cries in horror.
• Series Fauxnale: The Jerkinators! was intended to serve as a series finale for both Jimmy Neutron and The Fairly OddParents, but the latter ended up getting renewed for five more seasons while the former ended up getting a spin-off.
• Shaking the Rump: In "When Nerds Collide!", this is one part of the "In your face!" dance done by both Jimmy and Anti-Cosmo.
• Shoo Out the Clowns: Carl and Sheen disappear from the first special before the final act, as the focus goes to Jimmy trying to stop Mr. Crocker from taking over Fairy World.
• Shout-Out:
  • Sanjay sarcastically calls himself Yogi Bear.
  • "Pay no attention to the fairies operating the fudge-head suit!"
  • "Say hello to my big glowing friend."
  • Cindy, when walking through Timmy's "lab" mentions Mr. Fusion.
  • Professor Calamitus imprisons Jimmy's family in Carbonite.
• Showdown at High Noon: Parodied in "When Nerds Collide!" during Jimmy and Timmy's "nerd fight" to see who takes Cindy to the dance.
• Skyward Scream: One delivered by Sheen once he and Carl see the real Jimmy in Timmy's world, realizing that Timmy is not Jimmy in disguise.
  Sheen: EVERYTHING I KNOW IS A LIE!
• Stop Hitting Yourself: In "When Nerds Collide" Calamitous shows to Jorgen that he's in control of their fused body by doing this to him.
• Story-Breaker Team-Up: In-Universe, this sets off the plot of the third movie. When Jimmy and Timmy team up, their Rogues Galleries don't fare well. This makes things boring, so they decide to literally Create Your Own Villain to get a challenge.
• Sure, Let's Go with That: Cosmo and Wanda let Jimmy think they're computer programs so he doesn't find out they're fairies. Timmy also goes with it when they return home in the end.
  Jimmy: Thanks for saving my dog.
  Timmy: Thanks for saving my...eh...
  Jimmy: Fairy programs?
  Timmy: Sure, fairy programs!
• Take a Third Option: The plot of When Nerds Collide revolves around Cindy whether to take Jimmy or Timmy to the Friday the 13th dance. In the end when she still can't decide, Jorgen, as a repayment for rounding up the anti-fairies and freeing him from Calamitous' control, solves the problem by creating portals at the dance so she can go with both.
• Tempting Fate:
  • In the second special, when Cindy's complaining about not having a date, Libby says that it's not like a date will crash through the ceiling. Cue Timmy Turner crashing through her ceiling!
  Timmy: [to Cindy] Hi, remember me?
  Libby: ...I must use this power for GOOD!
• Throw the Dog a Bone: Despite (understandably) having no reason to help Timmy after the latter switched universes with him and turned Goddard into a Killer Robot, Jimmy selflessly helps him win the science fair by sending Goddard to his world as a repayment for Timmy apologizing for what he did and fixing his mistakes.
• Time-Passes Montage: Shirley waiting at the mall in The Jerkinators. Parodied in that only an hour passed despite all the day/night and weather shifts.
• Time Stands Still: In the second special, this is the Anti-Fairies' master plan, with a bunch of them spin around the world to halt its rotation so that Friday the 13th never ends.
• Turn the Other Cheek: Jimmy forgives Timmy for being a jerk to him when they first met, in addition to knowing how he isn't as smart as him when he saw all the Fs he got from Mr. Crocker.
• Ultra Super Death Gore Fest Chainsawer 3000: "The Decimator", Timmy's video game about blowing the world up, rated "Triple-G for Gratuitous Gutwrenching Gorefest", which he installs into Goddard, accidentally turning him into a Killer Robot.
• Unsportsmanlike Gloating: AJ spends the whole first special boasting to Timmy (and later Jimmy) that he and his clones are going to kick his butt at the science fair and taunting him for not even getting started on his own project. Thus, he gets some Laser-Guided Karma when Jimmy sends Goddard to Timmy's world and he acts as Timmy's project, with Timmy being given 1st Place and declared smarter than AJ and his clones.
• Unusually Uninteresting Sight:
  • In the third movie, Chester and AJ never question how Timmy made friends with a person from another universe, nor do they question the kid-sized adults with green and pink hair following him around.
  • Normally viewers of the show aren't weirded out by Timmy talking to inanimate objects due to them being Cosmo and Wanda in disguise. It is, however, portrayed realistically when Timmy is caught talking to them by three female classmates of his.
    Red-haired girl: Oh, my gosh, It's that boy who talks to inanimate objects! Just smile and back away slowly... (her and the other two girls back away)
• The Villain Must Be Punished: In the first special, after Jimmy turns Crocker into several lab objects until the latter surrenders. Jorgen (who was earlier turned into a schnauzer by Crocker) replies it's not enough punishment for de-powering Fairy World and trying to take over it and proceeds to maul Crocker.
  Mr. Crocker: Hey! I surrender! Enough!
  (Jimmy turns him back into his human form with Jorgen's wand)
  Schnauzer Jorgen: No, it is not enough. Get ready, tiny human, as I shred your memory to bits with my muscular canine teeth. (Jumps at Crocker)
• Villain Decay: Denzel Crocker was the main villain of the first power hour. Then look at him in the others.
• Villain Team-Up: Anti-Cosmo and Professor Calamitous in the second. Interestingly, while Anti-Cosmo is the one who ends up indulging in a double-cross, Calamitous is the one who ends up being the Final Boss.
• Wham Line: In the first installment:
  • During the fight against Crocker in Fairyworld, Jimmy gets hit by a wand and his head somehow springs. Cue Cosmo and Wanda appearing in the window of the mech suit.
    Wanda: Technically, he's not even Jimmy Neutron.
  • Done earlier in-universe, when Jimmy appears on Goddard's communication window, Cindy exclaims, "It's Neutron!"; thus in turn leads to Carl and Sheen realizing Timmy was not Jimmy in disguise.
• What Happened to the Mouse?: Other than the previously mentioned hypnotism in the first special, In "When Nerds Collide", Timmy changes the sign in Crocker's lair to read The Timmy Cave, in order to convince everyone it is his lab. This is never undone.
• What Measure Is a Non-Human?: Because Jimmy believed Cosmo, Wanda, and the entirety of Fairy World was a computer simulation, he was totally willing to leave and let Crocker wreck it. It takes Timmy reminding Jimmy of Goddard and seeing Cosmo and Wanda in total fear to make him change his mind.
• What the Hell, Hero?: In the first special, Timmy and Jimmy call each other out during the climax.
  Timmy: You brought Mr. Crocker to Fairy World?! What kind of genius are you?!
  Jimmy: You scrambled my dog's atoms and let a girl in my lab?! What kind of genius are you?
  Cindy: Back off, Nerdtron. Timmy here has already saved the day, and saved your dog, in half the time you would have.
  Timmy: Look, I need you to-
  Jimmy: Like I care about what you need. As long as my dog's okay, we're done.
  Timmy: NO! [Jimmy hangs up]
• Wrong-Name Outburst: In The Jerkinators.
  Timmy: Cosmo, you idiot! I'm sorry, force of habit. Jimmy, you idiot!
• Why Didn't I Think of That?: In the first special, When Jimmy sends Goddard to pose as Timmy's science project, winning the latter first place, an annoyed A.J. asks his clones how none of them thought into building a robot dog as a project.