''Scooby-Doo 2: Monsters Unleashed'' is the 2004 sequel to the 2002 live action movie ''Film/ScoobyDoo''.

Mystery Inc. is attending the grand opening of a museum based on their adventures and the monsters they caught. However, the celebration is cut short due to the Pterodactyl ghost attacking and stealing two different costumes. As it turns out, someone is using a machine to reanimate the monster costumes and turn them into real monsters.

The film is noticeably more kid-friendly than the first film, and was an even worse failure critically (winning a Razzie for "Worst Remake or Sequel"), and grossed around $180 million, making a profit, but not as much as Warner Bros. had expected. While this did signal the end of the full feature films, Warner would go on to make two live action made-for-TV prequels five years later: ''Film/ScoobyDooTheMysteryBegins'' and ''Film/ScoobyDooCurseOfTheLakeMonster''.

This was the final life-action Creator/HannaBarbera adaptation to be overseen by co-founder Joe Barbera, who died a year later.

See the ShoutOut page [[ShoutOut/ScoobyDoo here]].

!''Scooby-Doo 2: Monsters Unleashed'' provides examples of:

* AdaptationalBadass: Almost all of the classic Scooby-Doo monsters and Mystery Inc. are much more battle competent.
* AdaptationalComicRelief: The Skeleton Men were originally ominously eerie villains in the cartoon, but in the film they're the StupidEvil duo who fail at their objectives.
* AdaptationalVillainy: The monsters are much more AxCrazy in the film than they were in the cartoon.
* AllThereInTheManual: The featurette "True Ghoul Hollywood Stories" reveals the Cotton Candy Glob's true first name: Timmy.
* AmbiguouslyGay: [[spoiler:While under the guise of Heather Jasper Howe, Jacobo flirted with Fred and was mentioned to have cuddled with Ned]].
* AxCrazy: The monsters are actively trying to murder Scooby and the gang as opposed to chasing them away.
* BadGuyBar: The "Faux Ghost" is a hangout for criminals the gang had unmasked before where they casually make fun of Mystery Inc such as sticking them on a {{Dartboard of Hate}} or playing a Wack-A-Mole variant of them.
* BigBad: The Evil Masked Figure, a.k.a. [[spoiler:Jonathan Jacobo]].
* BigNo: The Evil Masked Figure as they are unmasked.
* BlindWithoutEm: Velma, naturally. This time it's somewhat downplayed, as even after she [[DroppedGlasses loses them]], she's still able to make out [[spoiler:Patrick's StalkerShrine to Jonathan Jacobo, as well as the photograph showing [[NotQuiteDead the supposedly dead Jacobo]] outside the half-finished Coolsonian Museum]].
* BrainBleach: [[spoiler:Ned the cameraman knew who the Evil Masked Figure was. What he doesn't know, however, is that she is a ''he''.]]
* BroadStrokes: The film pretty much ignores the events of the 2002 film.
* {{Buffyspeak}}: Also counts as ActorAllusion for Daphne.
--> '''Daphne''': Taste the pain, mr. glow-y, ugly, thing!
* TheCameo: Scooby drank a potion that turns him into the Tasmanian Devil.
* CanonForeigner: The Cotton Candy Glob was created for the movie and never appeared in any of the Hanna-Barbera cartoons.
** Actually, it was inspired from an episode of ''The Scooby-Doo Movies'' where two green candy globs were haunting Mama Cass's candy factory.
** While a Pterodactyl Ghost exists in ''The Scooby-Doo Show'', the culprit is a man name Johnny whose motif involves music pirating. Johnathan Jacobo doesn't exist in any of the cartoons and is considered a separated person than Johnny who also took the identity of a Pterodactyl Ghost.
* CharacterDevelopment: Shaggy and Scooby are trying to become legitimately competent detectives as opposed to the screw-ups they always thought they were. Naturally, they succeed by the end of the film.
* CoDragons: The Pterodactyl Ghost and Black Knight Ghost serve as commanders to the Masked Man.
* ContinuityCavalcade: The Coolsonian Criminology Museum has the costumes of several villains from ''WesternAnimation/ScoobyDooWhereAreYou'', ''The Scooby-Doo Show'', and ''WesternAnimation/APupNamedScoobyDoo'' on display.
* ContinuityNod: In the cartoon, Captain Cutler was defeated by having a vehicle crash into him. In the film, he's also defeated by having a vehicle crash into him.
* CorruptCorporateExecutive: While Jerimiah Wickles isn't the BigBad, or even affiliated with him in anyway, he's still a slimy {{jerkass}} who is in the process of wooing investors to help him create a summer camp where kids would work nearly 20 hours a day mining for gold. He justifies it by saying the kids would have the time of their life learning about The Gold Rush and living like real miners, while he and the investors will get free labor.
* DancePartyEnding: The Movie ends with the characters dancing to ''Shining Star'' by Earth, Wind and Fire.
* DramaticUnmask: Done [[spoiler:twice]] with the Evil Masked Figure, unmasking them as [[spoiler:Heather Jasper-Howe, then unmasking ''Howe'' as actually being Jonathan Jacobo in disguise]].
* TheDreaded: The Pterodactyl Ghost, which is easily the most threatening villain in the movie (besides the [[BigBad Masked Man]]). Daphne even calls it "the dreaded Pterodactyl Ghost" in the opening scene.
** The Tar Monster comes close in killing the gang closer than any other monsters in the movie.
* DroppedGlasses: Velma drops her at one point towards the end of the film. She lampshades it, remarking, "I have ''got'' to consider contact lenses." Her glasses are soon picked up by Patrick.
* EatingTheEnemy: Scooby and Shaggy hide in a room to escape some monsters and in that room is a giant Cotton Candy monster. Too bad for the monster, the BigEater duo take care of it by doing what they do best.
* ExpressiveMask: The Evil Masked Figure's mask. [[spoiler:And [[LatexPerfection the Heather Jasper-Howe mask they wear underneath it]]]].
* EyeScream: Old Man Wickles, a.k.a. The Black Knight Ghost threatens Shaggy and Scooby that if he he ever caught them and the rest of Mystery Inc., he'd tear out their eyes, and make them eat one, while leaving the other one unharmed so they could watch themselves eating one of their own eyes. Ironically when he threatens them, he doesn't know who they were, and before that has given them advice on leaving the criminal life while they have a chance, because he believes that they are wannabe criminal fanboys, that he has just met at a BadGuyBar called The Faux Ghost, which is a hangout for all of Mystery Inc's defeated and unmasked villains.
* FakingTheDead: [[spoiler:the gang actually catches on so quickly that Jonathan Jacobo may be the villain they're after from the clues: he did have designs of a machine that can create real monsters, ''and'' it was his alter-ego, the Pterodactyl Ghost, that attacked the museum and set the whole thing in motion. The only reason they brush this aside is because Jacobo is believed dead after attempting to escape prison.]]
* FlyingWeapon: The Black Knight ghost does this with his sword, smugly quipping "Look, no hands!".
* {{Foreshadowing}}: If you can understand Daphne's "incoherent babble" when she confronts Heather Jasper-Howe, you'll realize [[spoiler:she's figured out that Howe is actually the Evil Masked Figure]].
* {{Foil}}: The Faux Ghost to [[spoiler:Jonathan Jacobo]]. While the patrons of The Faux Ghost are still bitter about being unmasked, they saw the error in their own ways too and are turning their lives around (though in Jeremiah Wickles' case he is still not a good man as shown by his plan for a gold mining camp) but still trying to abide by the law nonetheless. [[spoiler:Jonathan Jacobo]] however let his bitterness draw him down an even darker path of revenge and disregard for anyone but himself and ultimately made things worse for himself considering he went to prison with a probably more serious sentence since he attempted to kill several people.
* FrameUp: [[spoiler:Jacobo tried to frame his old hated cellmate Old Man Wickles by putting the book he used to create the real monsters and The Black Knight Ghost in Wickles' home for Mystery Inc to find.]]
* GroinAttack: Velma delivers one to the Black Knight Ghost after determining that it is his only weakness.
* HateSink: Good luck finding any fans of Heather Jasper-Howe [[spoiler: AKA Jonathan Jacobo]]. Her snobbish attitude and her trash-talking of Mystery Inc. make her an unlikable character in this film.
* HeroesWithBadPublicity: Mystery Inc. becomes these courtesy of Heather Jasper-Howe.
* IJustWantToBeBadass: A subplot in the film is how Scooby and Shaggy want to stop being TheLoad for the rest of Mystery Inc.
* LatexPerfection: [[spoiler:Jacobo masquerading as Heather.]] Hilariously subverted immediately afterwards when Fred confronts [[spoiler:Jacobo's]] accomplice:
-->'''Fred:''' And the real identity of Ned is... ''[pulls at Ned's hairline]''\\
'''Ned:''' Ow!\\
'''Fred:''' ...Ned!
* LegionOfDoom: Several famous monsters Mystery Inc. have tackled become lackeys to the Evil Masked Figure.
* LetsSplitUpGang: When the group arrive at Wickles' mansion, it's ''Shaggy'' who says this (as part of his drive to be a better detective).
-->'''Shaggy:''' Alright, gang! Let's, like, split up, and look for clues.\\
''[the gang split up]''\\
'''Fred''': [[LampshadeHanging He stole]] [[BuffySpeak my thing]] [[CatchPhrase that I say]]!
* ManipulativeBitch: Heather Jasper-Howe manages to start a smear campaign to discredit Mystery Inc. [[spoiler: This is because she is actually Jonathan Jacobo doing this out of revenge.]]
* MindOverMatter: The Black Knight Ghost now has the ability to move his sword with his mind, which causes some trouble for Daphne after knocking it out of his hands.
-->'''Black Knight Ghost:''' Look! No hands!
* MotorcycleJousting: Fred rides a motorcycle to duel a knight ghost.
* MythologyGag: When Scooby [[ItMakesSenseInContext finds the toilet brush in Wickles' mansion]], he and Shaggy start singing into it. The song? "Strangers in the Night" by Frank Sinatra, the song from which Scooby's name was derived.
* NeverFoundTheBody: When telling the gang about Jonathan Jacobo's failed prison escape, Velma explains that "his body was lost at sea". [[spoiler:Only it turns out Jacobo is NotQuiteDead]].
* NotAMask: [[spoiler:The guy working for the Evil Masked Figure is Ned, who Fred once tried to pull his mask, only to reveal it's actually him.]]
* OhCrap:
** The Cotton Candy Glob when he realizes that Scooby and Shaggy are NOT afraid of him. On the contrary...
** The Black Knight Ghost invokes this word for word when he notices that Fred and Daphne have just [=MacGyvered=] a way to defeat both him and the 10,000 Volt Ghost at the same time.
* OneManArmy: The Tar Monster can be this due to the nature of his powers, especially during the climax when [[spoiler:he single-handedly incapacitates all four human members of Mystery Inc.]]
* NiceJobBreakingItHero: Shaggy and Scooby accidentally create even ''more monsters'' while fiddling with the machine. This includes creating [[OurZombiesAreDifferent Zombie]], [[KillItWithFire Miner 49er]], [[EliteMooks Captain Cutler]], and the [[OneManArmy Tar Monster]].
* PantyShot: Velma has one for a couple of frames as she jumps into a ship's air funnel.
* PaperThinDisguise: Shaggy and Scooby infiltrating [[BadGuyBar the Faux Ghost]] as "Shizzy [=McCreepy=]" and "SD [=McCrawley=]" respectively. Astonishingly, it works -- right up until Scooby's afro flies off.
* PsychoElectro: The 10,000 Volt Ghost.
* PsychopathicManchild: The Black Knight Ghost invokes this when Fred tries to stall him by TalkingTheMonsterToDeath. He has Fred and Daphne at his mercy, Fred claims that he's using a brutal façade to hide his true sensitive nature. The Black Knight says "you have touched my inner child, and HE'S REALLY MAD!"
* PteroSoarer: Double subverted; the Pterodactyl ghost is obviously not supposed to look like a real pterodactyl. However, Velma analyzes one of its scales to find that it's "a ''real'' pterodactyl scale". Real pterosaurs didn't have scales (they had hairlike fibers on their bodies).
* PunctuatedForEmphasis: Before Scooby [[spoiler:resets the control panel to the machine]], he says to the Evil Masked Figure after the latter asks who does he think he is:
-->'''Scooby:''' SCOOBY...DOOBY...DOO!!!!!
* QuoteMine: Heather Jasper Howe does this to Freddie twice, which helps build onto Mystery Inc.'s bad press.
--> '''Freddie:''' Hey! You're doing that thing again where you take everything I say out of context. You're trying make it look like I think Coolsville sucks.[''Remembering that he's being filmed''] No, don't record that!
* RedHerring:
** [[spoiler:Velma's LoveInterest, Patrick, who has a StalkerShrine to [[BigBad Jonathan Jacobo]] located not far from the Evil Masked Figure's lair, and even admits to having admired the latter's work]].
** Also Jeremiah Wickles, who used to be the Black Knight.
* TheReveal: [[spoiler: Dr. Jonathan Jacobo is the BigBad all along and secretly posing as reporter Heather Jasper-Howe so he can tarnish Mystery Inc.'s reputation.]]
* RiddleForTheAges: So how does the machine used to bring monster costumes to life work? We don't know and it's never answered.
* {{Sadist}}: The Evil Masked Figure and his monsters try to make Mystery Inc. suffer ''before'' Tar Monster can finish them off.
* SelfDisposingVillain: Non-lethal example. [[spoiler:The Evil Masked Figure ends up captured by tripping on his own catwalk.]]
* TheStinger: Scooby [[CelebrityParadox is playing the Game Boy Advance game based on the movie]] and shows the viewers a secret code to use in the game.
* TookALevelInBadass: SCOOBY-DOO. [[spoiler: He kills all the monsters in the climax himself.]]
* TokenHuman: The Evil Masked Figure is the only human among the LegionOfDoom of former Scooby-Doo monsters.
* TruerToTheText: Compared to the first film.
* UnsettlingGenderReveal: [[spoiler: Heather Jasper Howe (Alicia Silverstone) is really a man.]]
* WhoIsDriving: Fred tells Shaggy to drive the van while he and the girls try to fend off the Pterodactyl Ghost chasing them.
-->'''Fred:''' This is bad!
-->'''Shaggy:''' No doubt.
-->'''Fred:''' Shaggy?
-->'''Shaggy:''' Yeah?
-->'''Fred:''' Who's driving?
-->'''Shaggy:''' Uh...
-->''(the gang looks behind and notices that Scooby is the only one sitting in front)''