Phineas and Ferb head to the Tri-State Area's annual sci-fi and fantasy convention to meet their hero, special effects guru Clive Addison. Their plan gets sidetracked when they're swept into a duel between the fantasy fans and the sci-fi geeks. Meanwhile, Candace tries to keep secret that she's a fan of Ducky Momo, another convention staple. Across the convention hall, Dr. Doofenshmirtz has taken television executive Jeff [=McGarland=] hostage so he can pitch him a show he's developed, "Doof 'n' Puss."

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!! Tropes:

* AcquiredErrorAtThePrinter: The rare Ducky Momo collector's plate reads "I hate people!", as a result of accidentally printing the wrong saying.
* ActorAllusion: Doofenshmirtz (played by series co-creator Dan Povenmire) attempts to pitch his show to Jeff [=McGarland=] (played by Creator/SethMacFarlane). Dan Povenmire himself used to work with [=MacFarlane=] on ''WesternAnimation/FamilyGuy''.
* AllForNothing: Candace finally buys a rare piece of Ducky Momo merchandise, a commemorative plate with [[AcquiredErrorAtThePrinter the wrong saying printed]] ("I hate people"), but once she sees the monster her brothers created, she breaks it. But at least she got some acceptance from Jeremy when she outs herself as a closeted Momo fan to him.
* ArgumentOfContradictions: Finkies! Speckies! Finkies! Speckies! Finkies! Speckies!
* BattleThemeMusic: "Our Movie's Better Than Yours".
* BlatantLies: Candace tells her mother that she is going to Stacy's and the big bag she is carrying has smaller bags. (Supposedly, it's actually her Ducky Momo costume.) She also tells Jeremy she's hanging with Stacy and tells Stacy she's hanging with Jeremy.
* BorrowedCatchphrase: After rejecting the suggestion of "giving the platypus a girlfriend", Doof borrows Candace's catchphrase, "My artistic integrity and I are out! PEACE!"
* TheCameo: The Talking Zebra appears briefly in the simulation sequence at the beginning, holding a picture of Candace emulating the UsefulNotes/BarackObama "HOPE" mural.
-->'''Talking Kevin''': I voted for ''you'', Kevin.
* CatchphraseInterruptus: When Phineas and Ferb arrive at the convention, Phineas begins to say, "Hey!", but then we cut to a sepia-toned drawing of Perry and we hear...
-->'''Doofenshmirtz''': "Where's Perry" is written on this wanted poster, hanging on a tree. And we see this little hand reach up and tear the poster down and the music kicks in and all, "Chicka, chicka, chow, chicka, chow, chow, chicka, chicka, chicka, chicka, chow," and the opening credits start, like on one of those cool 80's TV shows with a voice over. You know...
* CelebratoryBodyTossing: After Candace (dressed as Ducky Momo) "defeats" the monster, all the convention goers toss her into the air, celebrating how "Ducky Momo" saved them from the monster. Subverted when Candace reveals herself to be the one wearing the Ducky Momo suit, causing the nerds to put her back down and laugh at her for liking such a childish property.
* ClosetGeek: Candace is revealed to be one for a young children's cartoon show titled "Ducky Momo"; she attends the annual convention looking for rare Ducky Momo merchandise wearing a full Ducky Momo costume, so that no one would recognize her.
* DescriptionCut: Baljeet, a Speckie, asks Phineas if he has even ''met'' the Finkies leader.
-->'''Buford''': I'm sure you're wondering why I, Buford, have taken a leadership role in such a geek-centered enterprise. Well, take a look around! This place is crawlin' with nerds! I'm like a kid in a candy store! Plus, I relate to the character of Odoff Underhump and his complex emotional inner journey.
* DramaticallyMissingThePoint:
** When Phineas and Ferb are about to greet Clive Addison and show their special effect demo, they are interrupted by Irving and Albert, who inadvertently distract them long enough for Clive to head off, causing Phineas to sigh in disappointment. Irving takes this to mean that Phineas (who is dressed as a "Space Adventures" captain) is upset that Ferb (dressed as an Elf from "Stumbleberry Finkbat") is picking fantasy over sci-fi.
** Clive reveals to Phineas and Ferb that he became a special-effect producer for "Space Adventures" and "Stumbleberry Finkbat" to bring people together. Instead, the respective fans of both films have a strong FandomRivalry.[[invoked]]
* EnemyMine: Invoked by Phineas, Ferb, and Clive by creating a giant monster with special effects to make both sides work together.
* EvenNerdsHaveStandards: Even before the two fandoms called a peace, they both share a disdain for the children's show Ducky Momo, much to Candace's shame.
* ExecutiveMeddling: InUniverse. The producer Doofenshmirtz pitched his show to agreed (after being held hostage) to greenlight his idea, but asks that the platypus should get a girlfriend. Doofenshmirtz is furious at the idea and walks away, saying he refuses to be a SellOut. The show was made anyway, and Doof lampshades at the end that they were probably right. [[MythologyGag It was also a production in-joke, as "give the platypus a girlfriend" was an actual suggestion given by Disney]] when ''Phineas and Ferb'' was first pitched.
* ExpositoryThemeTune: The theme for ''Doof 'n' Puss'' is presented in the style of action shows from the 1980s, such as ''Series/TheATeam''. See WunzaPlot.
* FandomNod: Candace being a closeted fan of Ducky Momo can be seen as an acknowledgement of the adults who enjoy ''Phineas and Ferb''.
* FandomRivalry: In-Universe between the fans of "Space Adventures" and "Stumbleberry Finkbat." This is against the wishes of their producer Clive.
* FreezeFrameBonus: One of the background wizards is dressed like Wade from Kim Possible's fantasy video game episode.
* HumansAreSmelly: Buford tells the Speckies to "Smell [his] barbarian pits".
* HypocriticalHumor: Doofenshmirtz throws in a random monster to wrap up his TV show pitch. The TV exec calls him out on it as "shoddy writing" — just before a random monster attacks the convention hall immediately afterward.
* ImplausibleDeniability: When the cashier at the Ducky Momo stand asks Candace, who is wearing a Ducky Momo costume, if she is fan, she simply replies, "No. Why do you ask?"
* TheMagicVersusTechnologyWar: Played with. Phineas and Ferb head to the Tri-State Area's annual sci-fi and fantasy convention where a duel between the fantasy fans and the sci-fi geeks ensues.
* NerdyInhaler: As the two warring fandom armies march, some of the members among them briefly use their inhalers.
* NobodyHereButUsStatues: Candace hides from Suzy in an alien nest pretending to be one of the eggs.
* OneWingedAngel: Doof's show has the shapeshifter pretending to be the mayor turns into a monsterous giant, which Jeff [=McGarland=] lampshades as [[DeusExMachina lazy writing]], only to change his mind after seeing Phineas and Ferb's giant holographic monster.
--> '''Jeff''': Having monsters come out of nowhere at the end of stories is lazy story writing.
* PardonMyKlingon: "To quote Lump Sharkboard from ''Space Adventure 16''... 'glorf'."
-->'''Heavenly Choir''': Glooooooooooooooorf!
* PunnyTitle: Tonight's episode of ''Doof 'n' Puss''... "Ham on Rye, Hold the Mayor"!
* SawAWomanInHalf: In the "Doof 'n' Puss" pitch, Doofenshmirtz and Perry attempt to infiltrate the city hall and figure out what the mayor is up to by pretending to be a magician act, with Doofenshmirtz attempting to cut Perry in half. After they've been found out, Perry hops out of the box, his two halves actually separated but himself still alive.
* ShowWithinAShow:
** The film franchises, sci-fi oriented "Space Adventures" and fantasy oriented "Stumbleberry Finkbat", are a source of conflict between the two fandoms.
** There's also "Ducky Momo", a child-aimed program that Candace enjoys.
** A variant is the show ''pitch'' Doofenshmirtz created to rally his own fandom, "Doof 'n' Puss".
* ShoutOut:
** The ''Space Adventure'' series appear to be a combination of the ''Franchise/StarWars'' films and ''Franchise/StarTrek'' films and series, while the ''Stumbleberry Finkbat'' films are clearly based on the ''Franchise/LordOfTheRings'' films.
** Looks like Doof [[Film/{{Airplane}} picked the wrong day to stop carrying garlic scented throwing stars.]]
* SillyReasonForWar: The two fandoms declare an all-out war in the convention hall to settle on which film franchise is better.
* SpecialGuest: Creator/KevinSmith as VFX artist Clive Addison and Creator/SethMacFarlane as TV executive [[NoCelebritiesWereHarmed Jeff McGarland]].
* StuffBlowingUp: Parodied. In Doofenshmirtz's "Doof 'n' Puss" pitch, Doofenshmirtz and Perry's fight against the vampire ninjas in the city hall gets interrupted by shots of completely random objects, such as a wooden house, a boat and a bowl of fruits, exploding.
* StylisticSuck: ''Doof 'n' Puss'' may look cool with its sepia-toned picture and well-performed fight sequences, but it still doesn't cover the fact that the concept and writing is über-ridiculous.
* ThisMeansWar: Baljeet declares war after the peace talks, which were a TrojanHorse, falls apart.
* ThrowTheDogABone: For once, Suzy is not antagonizing Candace, but only because she is dressed as Ducky Momo, which she is a fan of.
* ATruceWhileWeGawk: The warring fandoms stop for a moment when Candace (dressed as Ducky Momo) walks in between them to reach a rare merchandise.
* WunzaPlot: What Doofenshmirtz's "Doof 'n' Puss" pitch is about:
-->'''Announcer''': A fugitive-semi-aquatic-Special Forces-amateur stage magician, [[Series/TheATeam framed for a crime he didn't commit]] -- the 1865 assasination of UsefulNotes/AbrahamLincoln -- joins forces with a [[NinjaPirateZombieRobot rogue-trillionare-inventor-extreme fighting champion from the future]]! Together with the aid of R.I.C.K, their [[CoolCar super-crimefighting-high tech-talking rickshaw]], they'll bring hope, justice, and varying degrees of aquaticness to a Tri-State Area in peril!
* YouAndWhatArmy: Buford asks this after Baljeet's BaitAndSwitch peace accord turns out to be a declaration of war, but Baljeet says that doesn't make sense.
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