History Main / AirVentPassageway

!!Example Subpages:

* AirVentPassageway/WebComics

!!Other Examples:

Compare AbsurdlySpaciousSewer for a similar trope which takes place beneath buildings rather than in them. Also see ChimneyEntry.

* To this day, criminals will attempt this trope at any number of buildings where they can find a suitable opening. The difficulty they will encounter is that ducts don't stay the same size or shape all that often. The added difficulty of straight up-and-down ducts will see many criminals slipping and falling to become wedged or even killed by the fall. Even worse for some criminals is they may attempt this on holidays or weekends to avoid being heard clambering through the ventilation. When they become trapped, they must wait days without food or water in extremely uncomfortable positions for somebody to discover them. Given that some buildings are closed for months at a time (if not permanently), it's not surprising that several unlucky burglars have ended up ''dying of thirst'' or exposure before being found when people finally return and notice a smell, or sometimes aren't discovered at all until the building undergoes maintenance or is demolished.

%% Image selected per Image Pickin' thread: https://tvtropes.org/pmwiki/posts.php?discussion=1574295258028572600
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[[quoteright:350:[[WesternAnimation/RegularShow https://static.tvtropes.org/pmwiki/pub/images/regular_show_mordecai_and_rigby_in_the_vents.png]]]]

* An example of a villain using this trope is found in Marvel's 1990s series ''ComicBook/{{Sleepwalker}}'', when SerialKiller Jeremy Roscoe, after freeing himself from his restraints, climbs into the ducts to escape the prison hospital where he was being held. Probably not as bad as some of the other examples, since by that time the alarms were already activated and Roscoe's only concern was getting out by the fastest route possible.
* Franchise/SpiderMan does this every now and again. In an interesting variation, however, he usually does it when he's breaking ''into'' a place, rather than trying to escape.
* Kei tries this in ''The LightNovel/DirtyPair'' series ''Biohazard''. But she gets stuck when her full, child-bearing hips won't fit. Mmmm. It's a ShoutOut to one of the TV episodes. Also contains Yuri's wonderful 4th-wall-leaning/LampshadeHanging from her outside POV: "Been hitting the cheesecake a little too hard, hmm?"
* In the fourth issue of ''ComicBook/GothamCityGarage'', ComicBook/{{Supergirl}}, ComicBook/{{Nightwing}} and ComicBook/{{Catwoman}} crawl into a vent to break into a secret facility belonging to ComicBook/LexLuthor.
* Averted in ''ComicBook/YTheLastMan'' when Agent 355 and Yorick are breaking into a hotel in Sydney (surrounded by barbed wire and armed security due to the increase in drug-related crime AfterTheEnd).
-->'''Agent 355:''' You said we'd be able to use the air conditioning vents. They're six inches by four inches.\\
'''Yorick:''' Yeah, well, I overestimated the amount of... air this place might need...
* Reed Richards of the ''ComicBook/FantasticFour'' does this now and again as well. Justified in that his powers are to stretch his body to any length, and width.

* ''ComicBook/MsTree'' makes this escape as part of her DieHardOnAnX plot in the "New Year's Evil" story.
* In ''Webcomic/{{Dreamkeepers}}'', Namah and Mace (and Whip) are both partial to this trope.

* Subverted in "Earthquake", an issue of ''ComicBook/PaperinikNewAdventures'': Paperinik must get around a closed door. Being GenreSavvy, he tries to go into an airvent, remarking: "This always works in the movies!" Being a PintSizedPowerhouse, he can crawl in, but his large shield gets stuck.

* In a series of ''ComicStrip/GetFuzzy'' strips, Bucky tried this tactic to reach the ferret in the next apartment. While he fit fine (because he's a cat) he ended up getting lost and having to call for help... and Satchel mistook the voice coming out of the walls for God. HilarityEnsues.

* ''Dune: Chronicles of the Imperium'' main rules, adventure "Instrument of Kanly". The agents of House D'murjzin enter and exit the 35th floor of the Adici Enterprises corporate headquarters through an air vent.

* ''TabletopGame/{{Paranoia}}'' 1E supplement ''Acute Paranoia'', adventure "Outland-ISH". When the Troubleshooters are trying to get to ISH sector their High Programmer opponent tries to stop them by putting a convoy of vehicles across their path. They can get around this by finding and using an air vent passage.
* Creator/{{Chaosium}}'s ''ComicBook/ElfQuest'' RPG main rules, adventure "The Dying River". The elf {{P|layerCharacter}}Cs can get inside the troll tunnels by finding one of the airholes that the trolls use as a ventilation system.
* ''Encounter Critical'' supplement ''Asteroid 1618''. Small creatures can pass through The Vanishing Pyramid's ventilation system, but they must roll well or either get lost and exit in the wrong room or have to fight off packs of Raider Rats. If they survive they can scout out the contents of 2-8 rooms before having to roll again.
* ''Buck Rogers XXV (in the 25th Century)'' adventure [=XXVCA3=] ''Deimos Mandate''. When the pirates attack the [=RAM=] meeting, Mortimer tells the [=PCs=] to enter two air vent ducts and move around using them in order to ambush the pirates.
* ''TabletopGame/{{Shadowrun}}'' supplement ''State of the Art 2063''. HVAC (Heating, Ventilation and Air Conditioning) systems have ductwork that can be used by shadowrunners to infiltrate corporate buildings. Knight Errant Security recommends that the ducts be made too small to allow entry by intruders.
* ''TabletopGame/DungeonsAndDragons'', ''Literature/{{Dungeon}}'' magazine adventure "Granite Mountain Prison". One way for the PlayerCharacters to enter the title jail is to climb down the main ventilation shaft and pass through the air ducts in the facility until they can get to the cell of the prisoner they're trying to break out.

* ''TabletopGame/TechInfantry'' has a sequence where a space station is captured by rebels, and they lock Xinjao O'Reilly, the chief engineer on one of the space docks, in [[LockingMacGyverInTheStoreCupboard a tool storage closet]] with his engineering crew. They [[LampshadeHanging hang a lampshade]] on what a stupid move this is, grab a bunch of tools, and escape into the maintenance passageways between bulkheads. They make life very difficult for the rebels controlling the station for a while.

* ''Website/TheHardTimes'': "[[https://thehardtimes.net/culture/evil-villain-ensures-lairs-air-vents-extra-wide/ Evil Villain Ensures Lair's Air Vents Extra Wide]]", large enough to accommodate one adult man or a pair of sexy lady ninjas. The same villain also installs a LaserHallway.

* ''Film/{{Merc|Force}}s'' has this done by Varisa and Creed to sneak around the ship during the "Hijack" episode. At one point, one of the mooks tracks Varisa by the banging noises in the ductwork and ambushes her when she comes out.
* ''[[https://www.youtube.com/watch?v=hRTP2IZ2nOo Duct Hunt]]'', a parody of the ''VideoGame/MetalGear'' series made by Creator/RocketJump, deconstructs almost every aspect of this trope, including the way some players tend to use it in ''Metal Gear''.

* To this day, criminals will attempt this trope at any number of buildings where they can find a suitable opening. The difficulty they will encounter is that ducts don't stay the same size or shape all that often. The added difficulty of straight up-and-down ducts will see many criminals slipping and falling to become wedged or even killed by the fall. Even worse for some criminals is they may attempt this on holidays or weekends to avoid being heard clambering through the ventilation. When they become trapped, they must wait days without food or water in extremely uncomfortable positions for somebody to discover them. Given that some buildings are closed for months at a time (if not permanently), it's not surprising that several unlucky burglars have ended up ''dying of thirst'' or exposure before being found.

Most RealLife attempts to sneak in or out via air duct aren't very successful, since people tend to be fairly large and ducts tend to be fairly small, plus the fact that air can bend at ninety degree angles and fit through grates much more readily. There have been numerous cases where [[StupidCrooks enterprising criminals]] have attempted to rob a store by sneaking through the ducts and end up getting stuck. The usual ending is the embarrassed criminal being either pulled or cut out of the duct by the fire department and then promptly handed over to the authorities. That is if they don't crash through the ceiling when the vent gives way under their weight. A few unlucky individuals have gotten stuck inside the vents of buildings that were empty for days, weeks, even months (and the thief may have even chosen the building precisely for that reason), and wind up dying from exposure or thirst.

* To this day, criminals will attempt this trope at any number of buildings where they can find a suitable opening. The difficulty they will encounter is that ducts don't stay the same size or shape all that often. The added difficulty of straight up-and-down ducts will see many criminals slipping and falling to become wedged or even killed by the fall. Even worse for some criminals is they may attempt this on holidays or weekends to avoid being heard clambering through the ventilation. When they become trapped, they must wait days without food or water in extremely uncomfortable positions for somebody to discover them. Given that some buildings are closed for months at a time (if not permanently), it's not surprising that several unlucky burglars have ended up ''starving to death'' before being found.

Most RealLife attempts to sneak in or out via air duct aren't very successful, since people tend to be fairly large and ducts tend to be fairly small, plus the fact that air can bend at ninety degree angles and fit through grates much more readily. There have been numerous cases where [[StupidCrooks enterprising criminals]] have attempted to rob a store by sneaking through the ducts and end up getting stuck. The usual ending is the embarrassed criminal being either pulled or cut out of the duct by the fire department and then promptly handed over to the authorities. That is if they don't crash through the ceiling when the vent gives way under their weight.

Most RealLife attempts to sneak in or out via air duct aren't very successful, since people tend to be fairly large and ducts tend to be fairly small, plus the fact that air can bend at ninety degree angles and fit through grates much more readily. There have been numerous cases where [[StupidCrooks enterprising criminals]] have attempted to rob a store by sneaking through the ducts and end up getting stuck. The usual ending is the embarrassed criminal being either pulled or cut out of the duct by the fire department and then promptly handed over to the authorities.

!!Example subpages:

* [[AirVentPassageway/LiveActionFilms Film — Live-Action]]

* AirVentPassageway/{{Webcomics}}

!!Other examples:

[[folder:Film — Animation]]

* Used to escape a dead-end in ''Roleplay/SurvivalOfTheFittest'' by John Sheppard, Vera Lang and Kyrie Joseph, as killer Harry Tsai was hot on their heels and it was the only way out of the building they had run inside.
* Shelton and Ridgeway successfully do this in ''Roleplay/DarwinsSoldiers: Schrodinger's Prisoners''. It's also subverted in the third RP when Hans suggests this as a way to get into Pelvanida and James points out how that wouldn't work.

* ''Film/{{Merc|Force}}s'' has this done by Varisa and Creed to sneak around the ship during the "Hijack" episode. At one point, one of the mooks tracks Varisa by the banging noises in the ductwork and ambushes her when she comes out.
* ''[[https://www.youtube.com/watch?v=hRTP2IZ2nOo& Duct Hunt]]'', a parody of the ''VideoGame/MetalGear'' series made by Creator/RocketJump, deconstructs almost every aspect of this trope, including the way some players tend to use it in ''Metal Gear''.
* Kai tries to use one of these in the first episode of the ''WebVideo/ChroniclesOfSyntax'' to get out of the school. It doesn't quite work out how he expected.
-->'''Kai:''' Okay, this thing is ''definitely'' getting smaller. I might just hyperventilate myself into a coma down here. They'll find me years later, turning to dust in the fetal position. Can I even get into the fetal position? I don't care. Just keep moving. Just keep moving forward...

* Episode 1 of ''Podcast/TheOrbitingHumanCircusOfTheAir'' opens with protagonist Julian the Janitor's personal InteractiveNarrator describing Julian having managed to get backstage by holing up in a heating duct, preparing to sneak into the eponymous radio show's ballroom studio for the third time in a week.

* ''WebAnimation/MinilifeTV'': In "[[Recap/MinilifeTVSeason4Episode9 The Quarter Finals Begin]]", when Chris tries to bust Ian out of City Hall, he climbs into an air vent to get into his office.

* The ''Widow's Walk'' expansion set for ''TabletopGame/BetrayalAtHouseOnTheHill'' includes room cards which have dumbwaiters inside them; using one costs a movement space, but it allows you to go directly to the floor landing above or beneath you.

* ''Disney/LiloAndStitch'': This is how Stitch escapes from the prisoner bay after breaking out of his cell. Justified because he's small and fast, and all the guards know he's there, they just couldn't shoot him in time.

Most RealLife attempts to sneak in or out via air duct aren't very successful, since people tend to be fairly large and ducts tend to be fairly small, plus the fact that air can bend at ninety degree angles and fit through grates much more readily. There have been numerous cases where enterprising criminals have attempted to rob a store by sneaking through the ducts and end up [[StupidCrooks getting stuck]]. The usual ending is the embarrassed criminal being either pulled or cut out of the duct by the fire department and then promptly handed over to the authorities.

[[quoteright:350:[[WesternAnimation/RegularShowhttps://static.tvtropes.org/pmwiki/pub/images/regular_show_mordecai_and_rigby_in_the_vents.png]]]]

[[quoteright:217:https://static.tvtropes.org/pmwiki/pub/images/ventilation_shaft.jpg]]
[[caption-width-right:217:Why this trope [[RealityEnsues doesn't work]] in RealLife.]]

!!Examples:

* ''Wiki/SCPFoundation'', [[Characters/SCPFoundation [=Characters/SCPFoundation=]]]

-->-- [[http://www.avforums.com/threads/the-hollywood-rule-book.32262 "Hollywood Rule Book,"]] Vanity Fair

* {{AirVentPassageway/Literature}}

* {{AirVentPassageway/Webcomics}}

[[folder:Anime & Manga]]
* In "Turnabout Prophecy" of the ''Franchise/AceAttorney'' manga, this is averted. The ventilation pipes themselves are too small to crawl in, but it is possible to crawl in the area where the pipes are.
* In ''Manga/{{Akira}}'', Kaneda tries to escape custody through the ventilation duct. He doesn't get far though.
* In ''Manga/AxisPowersHetalia'', '''Paint it White!''': Italy, Germany, and Japan pull one of these in order to escape the aliens currently chasing them. May or may not be {{justified| trope}} because they were in an alien mothership, with air vents about the size of an average person. They DID fall through at one point, and Germany got quite a few scratches to the face.
* Amusingly {{downplayed|Trope}} by [[{{Meganekko}} Jody Hayward]] in ''Anime/ElCazadorDeLaBruja''. She uses the vents to sneak into [[BigBad Rosen]][[TheChessmaster berg's]] office only to find that her hips are slightly too large to fit through them.
* Ryō and Saeko sneak into a jewel exhibit this way in ''Manga/CityHunter''. Ryō gets a heel in his forehead as a reward for his overly ardent MaleGaze.
* {{Justified|Trope}} on two occasions in ''Manga/DanceInTheVampireBund''.
** Akira making it through the massive vents and tunnels of the underground city beneath Tokyo Landfill #1 to escape the assassins hunting him makes sense (and he finds himself reminding his [[UndeadChild prepubescent rescuers]] that he is not as compact as they are).
** In an inversion from volume 7, after a ManchurianAgent locks down Mina's skyscraper-cum-palace the only person who can get to the security center via the way-too-small-for-anything-remotely-human vents is [[BattleButler Vera]] (who turns into mist and is obliged to [[FullFrontalAssault leave her clothes behind]]).
* While searching an enemy ship in ''Manga/FairyTail'' the Exceeds (who are about the size of a cat) are shown crawling through an air vent, wondering about the necessity of it and complaining about how narrow it is. When they ask why they're in there instead of searching the rooms like a normal person, Happy says [[RuleOfCool "No particular reason"]].
* ''Manga/FrankenFran'' has to cut off at least half her body in order to pull off a vent escape.
* {{Justified|Trope}} in ''Manga/FullmetalAlchemist'': shrimpy Edward is the only character who can fit in the air vents, and for him it's a tight fit. Which leads to further comedy as Ed has a complex for being TheNapoleon.
* ''Anime/FutariWaPrettyCure'' episode 10. Nagisa needs to get into a store being robbed so she can meet Honoka, since [[WonderTwinPowers they have to be together to transform]]. Extra points for doing it in the course of about five seconds with no equipment.
* In ''[[Anime/MobileFighterGGundam G Gundam]]'''s second episode, Domon sneaks through the ducts of Madison Square Garden and ambushes Chibodee's boxing opponent so he can take his place. In the 2010 manga re-telling, the sequence is PlayedForLaughs instead: Domon ''intends'' to go to Chibodee and challenge him, but [[IdiotHero ends up in the opponent's room because he got lost]]. [[RefugeInAudacity He then tries to play himself off as an autograph hound.]] It doesn't work, and after knocking the guy out he decides to take his place.
* Mamoru and Volfogg do this in ''Anime/GaoGaiGar'' when their base is taken over by a computer-hacking Zonder. Mamoru is a nine-year-old, but Volfogg is a ''robot that transforms into a police car''.
* ''Anime/GhostInTheShellStandAloneComplex''
** Like the opening of season 1, the opening of season 2 is all about showing off the awesome skills of Section 9 while providing a reason for the unit's reactivation. The regular SWAT unit attempts an assault on the Chinese embassy through the air vents, but spectacularly fails with one officer dead and another being added to the terrorists' hostages. Seeing these poor results, his superiors immediately give Aramaki the green light to send in his team and get the job done.
** When Batou is snooping around in Zaitsev's office, he hides in the ducts when Zaitsev returns unexpectedly.
** 2nd GIG episode "Ambivalence". Major Kusanagi physically breaks into the Cabinet Intelligence Agency's building to cyberhack into its Decatonchire server. After the BigBad Goda discovers the breach and alerts security, she escapes the building by entering the air system via a opening in the ceiling.
* ''Anime/{{Hellsing}}''
** Integra does this to hide from her uncle.
** Seras and Walter also use this to avoid a confrontation with the Valentine brothers.
** Walter actually makes a point of reminding Integra that she used the vents to hide, so it's possible that they were deliberately designed with the purpose of allowing people to move throughout the mansion and avoid enemies in mind.
* Done in ''Manga/HunterXHunter'', though the character doing this ([[spoiler:Queen Oito, after Kurapika [[SuperEmpowering grants her Nen abilities]]]]) is mind-controlling a cockroach, making it more plausible than normal. The cockroach finds [[spoiler:Prince Tserriednich's [[AttackAnimal Nen Beast]] within the ducts, forcing Oito to perform a quick mind-recall back to herself before the Nen Beast eats the cockroach]].
* In ''Manga/JojosBizarreAdventureBattleTendency'', the [[HumanoidAbomination Pillar Man]] Santana manages to get through a 4-by-20-inch, grate-covered vent by ''pulverizing every bone in his body and flattening himself'' until he can slip through. Thereafter, the Nazi research team does not live long enough to learn that EvilIsNotAToy.
* {{Subverted|Trope}} with glee in ''Anime/{{Mnemosyne}}'': Slender (though busty) ActionGirl Rin Asougi decides to infiltrate an empty research laboratory by going through the ducts. She predicts the [[LaserHallway lasers]] and makes them visible by filling the cramped ventilation duct with smoke from a cigarette, and then proceeds to slip under the lasers... until her butt catches the laser, setting off all the alarms. Cue Rin's capture and... {{Squick}}.
* In ''Manga/{{Monster}}'', Johan and Anna/Nina's mother escapes through a rather small-looking air vent not just pregnant but ''in labor''.
* ''Anime/NeonGenesisEvangelion'': Asuka, Rei, and Shinji were forced to use this route to get into the Geo-Front during a power outage when none of the doors would open. The air vent entrance also {{lampshade|Hanging}}d the MaleGaze when Asuka kept kicking Shinji for "looking ahead." Later in the episode, we are treated to the sight of ''HumongousMecha'' escaping via (humongous) air ducts. The geofront itself is an immense underground open space, hence the need for extremely large duct shafts to the surface to keep the air fresh.
* Done once in ''Manga/RaveMaster'' though by a creature who must be light, because he floats when he sleeps, and something that [[CallASmeerpARabbit may be a small dog]].
* In ''Manga/ShugoChara'', Kiseki and Yoru escape from a locked room this way. {{Justified|Trope}} since the Shugo Charas in that series are small enough to fit in normal air ducts.
* Successfully done by Tsukiyo in ''Manga/TheWorldGodOnlyKnows'', but small as she is she still couldn't have pulled it off normally. Rather, she was shrunk down to the size of a doll and it was still a pretty tight fit.
* Mokuba Kaiba once escaped from the Big 5 this way in ''Anime/YuGiOh'' At least he's a fairly small kid, more likely to fit and all that.
* In ''Manga/YuGiOhR'', Jounouchi and Honda avoid some {{Mooks}} this way. {{Lampshade|Hanging}}d by Jou, who complains about how claustrophobic it is and keeps getting accidentally kicked in the face by Honda.
* In ''Anime/YuGiOhArcV'', a few characters escape from prison this way. It takes them a while to remove the grate and the fans inside, and a guard catches them, but they manage to bluff that they had been ordered to repair it.
[[/folder]]

[[folder:Fan Works]]
* ''FanFic/CodeWings30'': Jeremie and the others use the ventilation shaft to their new room to evade the whitecoats and Erasers.
* ''FanFic/EpicTheThirdSurvivor'': Sherry spends several chapters roaming around the police station's ventilation system to evade the zombies.
* This is the method that Draco uses to get the Death Eaters into Hogwarts in ''Theatre/AVeryPotterMusical''.
* [[ZigZaggingTrope Zig-Zagged]] in a weirdly {{justified|Trope}} way in ''FanFic/HeroesOfTheDesk''--the air vents at a university facility are ''not'' large enough for a full-size human (averted), but a 14" tall Hero character can crawl through them (played straight--supercomputing buildings need a lot of cooling).
* [[http://www.fanfiction.net/s/4471204/6/I_Think_Some_Serious_Physics_Just_Happened One chapter]] of the ''WesternAnimation/KimPossible'' {{fanfic}} ''I Think Some Serious Physics Just Happened'' has a nice {{deconstruction}} of the trope when Ron, dropped into the real world, sneaks into a library through the airvents and naturally [[RealityEnsues gets dirty while crawling through them]]. Then he starts to wonder why the vents in the [[SupervillainLair supervillains' lairs]] were never less than spotless. Who was cleaning them? How? Why?
** It's often a good idea to clean out ventilation systems to increase air-flow efficiency, reduce allergens, and stop a significant layer of dust accumulating on everything in the building every night. Particularly in warehouses with the giant ventilation systems that someone could actually crawl through.
** Or there might simply be enough traffic in the ventilation system of the average villain lair to prevent dust gathering... Let's face it, those bases usually last a month or three, and see twenty-odd people getting around by air vents in that timeframe.
* In another ''Kim Possible'' fanfic, ''To Bebe or not to Bebe'', Kim and Ron are captured by a surprisingly competent villain who not only has air vents too small to crawl through, but also took all their equipment and destroyed it rather than leave it out to pick up when they escape.
* ''Fanfic/{{HERZ}}'': In chapter 4 Kurumi used a ventilation shaft to reach Terminal Dogma after being told it was off-limits.
-->''The grill made a tremendous clanging sound as it crashed onto the floor. Kurumi, in her UNIPF combat fatigues, emerged from the ventilation shaft. "Terminal Dogma is off-limits, my ass."''
* ''Fanfic/TheSecondTry'': Shinji used a ventilation shaft to sneak out and back in NERV in the second-to-last chapter.
* ''FanFic/NobodyDies'': Terrifying!Rei's favorite method of StealthHiBye is to drop out of [[strike:NERV's]] ''any'' ventilation system. ''He~eeey.'' OhCrap. Running now. Later revealed to be a trait common to all Lilith-based Nephilem, as when [[spoiler:Shinji is temporarily turned into a Nephilem, he suddenly gets good at zipping through vents too]]. Kensuke is picking it up as well, due to his... "friendship" with Rei.
* Used in the ''VideoGame/{{Portal 2}}'' fanfic ''FanFic/TestOfHumanity'', though it's more of an "incinerator exhaust pipe escape". Subverted in that [[spoiler:[[BigEater Wheatley]] is too fat to fit all the way through and ends up stuck, causing the pipe to explode from the built-up pressure]].
* In ''Fanfic/FalloutEquestriaPinkEyes'', the main character Puppysmiles is just a little filly, meaning it's easier to crawl around in tight spaces. She uses this to enter a locked-down fortress to search for her mom.
* Examples from Fanfic/{{the Calvinverse}}:
** Calvin ends up using one of these in ''Fanfic/RetroChill''.
** Inverted in ''Fanfic/CalvinAndHobbesTheSeries'': Andy and Sherman are ''captured'' by a [[TurnedAgainstTheirMasters possessed]] air vent.
* ''Fanfic/QueenOfAllOni'': Drago uses the air vents to break into Section 13. He calls it a cliche, and expresses disappointment that the Section 13 of the present isn't on the same level as the one in his time.
** During the FinalBattle, Jade and Hebi use the chaos of her forces' [[AllYourBaseAreBelongToUs invasion of Section 13]] as a distraction to sneak into the air vents and use them to get to the Vault unseen.
* ''FanFic/EarthAndSky'': After [[spoiler: Chrysalis]] is arrested and thrown in the dungeon in Los Pegasus, she slips free of her chains by [[spoiler: molting to filly-size]] and then crawls out through a vent. [[JustifiedTrope Even then, it only works because, as Luna points out,]] [[spoiler: [[JustifiedTrope her carapace hasn't hardened yet]]]], [[JustifiedTrope allowing her to squeeze through the tight space.]]
* ''FanFic/HitmanMiami'': In chapter 8, the only way into the target's office, apart from a locked steel door, is a six-inch wide vent in the ceiling, which Agent 47 uses to drop monkey chow into the room in order to lure in a KillerGorilla, then a grenade to kill the gorilla.
* In the ''VideoGame/{{Portal}}''[=/=]''WesternAnimation/MyLittlePonyFriendshipIsMagic'' crossover ''FanFic/BetterLivingThroughScienceAndPonies'', Chell uses some vents to get back inside the Enrichment Center. Justified in that her small pony body fits better.
* In ''FanFic/BlueSky'' it's not exactly air vents, but climbing in the chaotic crawl spaces of the facility.
* The absurdly spacious ones in Arkham are viciously {{lampshade|Hanging}}d in the ''Franchise/{{Batman}}'' fic ''FanFic/BruceHasAProblem''; evidently they were originally dog runs put in by a director who thought dogs would have mental healing properties, abandoned when the director died in a dog-petting accident. They were then repurposed as vents by another director, who was looking to cut costs to fund a step pyramid he was building.
* In the ''WesternAnimation/MyLittlePonyFriendshipIsMagic'' fanfic series ''FanFic/HarpflankAndSweets'' -- in the headquarters of the heroes, no less.
* Used for infiltration in the ''Franchise/MassEffect'' fic ''FanFic/MassesToMasses''. Subverted when Ian's weight brings it down, resulting in Melanis lecturing him on how this trope doesn't work in real situations.
** [[ThisIsReality "This is real life, not the vids."]]
* In the ''Series/StargateUniverse'' fic ''FanFic/{{Scribblings}}'', Chloe and Rush both make use of a variant of this: Chloe turns it into a prison for Eli and Rush turns it into a nest.
* In the ''VideoGame/SuperSmashBros'' fic ''FanFic/SmashGeneration'', this is how Midna went to see who was in the Mansion, and also how Pear, Riley, BJ and Popo evaded escape.
* This is Eric's favorite method of travel in the ''Series/{{Glee}}'' fanfic FanFic/SpahVerse, both at Dalton and [=McKinley=].
* In the ''[[Franchise/ShinMegamiTenseiPersona Persona]]''[=/=]''VideoGame/SuperSmashBros'' crossover ''Fanfic/SSBTheReturn'', Melody uses these to get around the school.
* In the MegaCrossover ''FanFic/SuperNetworkWars'' [[IdiosyncraticEpisodeNaming episode]] 27, some members of the Nueva Liga Filipina have to crawl through this in order to stop the poisons from being administered into the food of the [=VIPs=] at the 12th ASEAN Summit.
* Occurs in ''Anime/BubbleGumCrisis'' fanfic ''FanFic/TheBubblegumZone''.
* In the ''Literature/HarryPotter'' [[AlternateUniverse AU]] series ''FanFic/TheDarknessSeries'', Harry uses this when doing spy work at Riddle Manor [[spoiler: [[JustifiedTrope in snake form]]]].
* The ''WesternAnimation/ChipNDaleRescueRangers'' fic ''[[FanFic/TheMidnightverse Diamonds In The Desert]]'' is practically about this.
** Also from the same series, Zipper gets into and out of the National Institute for Mental Health via air vents in ''Lost And Found'', and the Rangers use the air-conditioning vents to get into Mr. Jacob's penthouse in ''Last Date''.
* The heroes use these to break into the base in the ''[[WesternAnimation/TheAdventuresOfJimmyNeutronBoyGenius Jimmy Neutron]]'' fanfic ''FanFic/TheOtherSideOfTomorrow''.
* Occurs in the ''Franchise/StarWars'' AlternateUniverse ''[[FanFic/ThePadmeAUs The Part to Be Played]]''.
* Part of the caper plans in the ''FanFic/UndocumentedFeatures'' fic ''Hellbringer and the After-School Special Mission Force #1: "The Bad Bank Caper"'' -- as Lain Iwakura says, "Oh, good... I was -hoping- we'd be hitting all the cliches on this job."
* This is how Carlos leaves the VILE base in the ''[[Literature/WheresWally Where's Waldo]]''[=/=]''Franchise/CarmenSandiego'' crossover ''FanFic/WhereOnEarthSpies''. He's a small dog, so it works.
* Used by the protagonists of ''Fanfic/YuGiOhForever'' during the last part of the Dueltropolis arc, to sneak on board the ARK.
* Calvin and Hobbes use this to infiltrate a base in ''Fanfic/TroubleIsland''.
* Justified in ''Fanfic/MassEffectHumanRevolution'': Ventilation passages in Krogan battle barges are huge because they're really meant for defenders to outmaneuver boarders.
* ''Fanfic/{{Equestrylvania}}'': In Book 2, after Rainbow Dash and Shatterstom are captured by [[spoiler: [[TheQuisling Rose Blade]]]], he has the former locked in a bathroom that's been converted into a holding cell/torture chamber; after getting free of her chains, she gets out of the room this way. Somewhat subverted, as it's a cramped fit, and Rainbow Dash is constantly worried that she's going to make noise and alert the {{Mooks}} below.
* ''Sailor Moon: Legends of Lightstorm'': In an attempt to bond with Sailor Mercury, Sailor Jupiter suggests that they get into a suspicious building by crawling in through the vents "like in the movies". Misunderstanding her intent, Mercury merely points out that the vents are probably too small for them to fit through.
* Averted in ''Fanfic/TheKeysStandAlone: The Soft World''. George talks about maybe navigating the air ducts to get to Mevaryat's basement room in the concert hall, but he isn't thrilled about the idea because he has no idea where the things go, and can't really navigate the larger world [[VoluntaryShapeshifting when he's something small]] anyway. Later, he finds out that the Tipaanese anticipated he might go in that way and set traps throughout the air ducts. Too bad for them he found a different way to get into the room.
* Lampshaded in ''FanFic/ChildOfTheStorm,'' wherein Clint (and later, Bucky) like to crawl around in them to get into HYDRA bases (or in Clint's case, just because he likes crawling around in the Avengers Tower ones). Tony freaked out the first time. Now, being [[TheGadfly Tony]], he still likes to pretend he has no idea of what's going on and send his robots to flush them out.
** In the sequel, Bucky notes that they'd be amazed at how many HYDRA bases he's broken into, a point he's apparently previously made to Harry. [[PersonOfMassDestruction Harry]], however, prefers [[DynamicEntry making his]] [[StuffBlowingUp own doorways]]. Or [[RefugeInAudacity using Doctor Strange as a chauffeur.]] As he loftily puts it, "One makes a statement, the other is economical.”
** On a related note, it's become solid fanon in the ''Avengers'' fandom that Clint likes doing this. A lot.
* Both played straight and deconstructed in the Batman fanfic [[https://www.fanfiction.net/s/8782654/5/Of-Friends-and-Foes "Of Friends and Foes."]] Robin and Kid Flash decide to sneak through air vents to eavesdrop on the JLA meeting for fun, and the size of the vents is explained away as being large enough for adults to come and work up there if a problem arises. However, it's noted that Robin still has to use his agility to get around, that it's pretty dirty, and that the boys have to keep their voices down to avoid being heard. Since [[{{Franchise/Superman}} one of the members]] has super-hearing and X-ray vision, [[{{Franchise/Batman}} one]] has HyperAwareness, and [[ComicBook/MartianManhunter another is a telepath]], it doesn't go too well anyway.
* In ''Webcomic/{{Narbonic}}'' fanfic ''A Brief Moment of Culture'', Artie hides from [[spoiler: a mind-controlled Mell]] in the ventilation ducts. Justified because tiny little gerbil; it's made clear a human would have trouble fitting an ''arm'' in the ducts. And then subverted when [[spoiler: Mell begins methodically smashing the ducts from one side to the other, which admittedly isn't something you can do with human-sized ones]].
* There are two instances in ''Fanfic/PokemonResetBloodlines''. Both of them are justified given that they involve relatively small Pokémon:
** The first, Ash's Aipom sneaks aboard the vents in Hunter J's airship, opening the doors for Ash and the others to get through to escape.
** The second, Ash's Snivy gets away from the Samurai by sneaking through the air vents of the battle club, and eventually seeing Ash and deciding to challenge him to see if he's the trainer she's looking for.
* ''FanFic/MermaidMelodyPichiPichiDuo'': In chapter 8, the group uses one to sneak into the aquarium and find the missing Hanon. It ends up backfiring on them when they [[SoMuchForStealth end up falling down a chute and landing heavily]].
* In ''Fanfic/AllGuardsmenParty'' the ''[[TheAllegedCar Occurrence Border]]'' has plenty such passageways. When Sarge tries looking for similarly-size vents on a properly-built space station, he's told nobody would ever build vents large enough to crawl through. The only reason the ''Border'' has such vents is because it's a very ''stupid'' ship.
* In Music/SpiceGirls [[AlternateUniverse AU]] Fic, ''Astral Journey: It's Complicated'', after getting sectioned, Melanie does this "twice". Her second attempts ends in disaster, leading to getting injured for real.
[[/folder]]

[[folder:Literature]]
* Played straight in a book based on the ''VideoGame/DonkeyKongCountry'' series, Donkey Kong was trying to get to a room containing an auto defense system in a building being built by Kremlings. As he tries to think of a way to get to the 8th floor without being seen, he hears guards coming, and goes into a nearby ventilation shaft. It's big enough to crawl through, and even has signs pointing him in the right direction.
* ''Literature/{{Animorphs}}'': Averted, since the one time this trope is used, Marco's in bug morph.
* ''Literature/{{Duumvirate}}'': The small kids who live in Northberg Educational Facility discover that they can go anywhere they want in the air vents. And the child-sized "secret" areas they lead to.
* Literature/JamesBond escapes confinement in ''Literature/DrNo'' through some ductwork, but he soon discovers that it was a purposefully-built series of hazardous obstacles (poisonous spiders, extreme heat, etc.), complete with viewports for entertainment, intended as a deliberate obstacle course set up by Dr. No.
* Justified in the sci-fi book ''Literature/{{Footfall}}'', as the aliens are twice human size and deliberately put the captured humans to work cleaning the spacecraft's air ducts. Their prison cell also doesn't contain a handy air duct, forcing them to escape before using the ducts to evade.
* In ''Illegal Aliens'' by Nick Pollotta and Creator/PhilFoglio, abducted humans on an alien ship hide in the air vents, because all the movies say that's what you do in that situation -- only they aren't air vents; they're conduits for a horrifically deadly gas weapon, which the aliens are preparing to flood throughout the ship, because they can't locate the humans....
* Something similar to the above happens in ''Literature/ArtemisFowl: The Arctic Incident''. Artemis has to crawl through a duct filled with fuel for the building's plasma weapons. Before his helmet runs out of air. Without being able to see where he's going. Knowing full well that if anyone turns on the plasma cannons, he's toast. Once he gets out, he has to be sprayed with anti-radiation foam or he'll likely develop cancer.
* Subverted in Creator/ChristopherBrookmyre's ''Literature/OneFineDayInTheMiddleOfTheNight''. After an earlier discussion of action movie tropes, one of the heroes spots the "Holy Grille" as the way out when they're held hostage. Unfortunately, he didn't reckon on the fact that crawling through metal ductwork is incredibly noisy, so everyone hears him as he tries to squeeze through.
* Justified in ''Literature/EndersShadow''. Bean uses the air ducts to explore and reconnoiter, but he can only do it because he designed a specialized workout to develop the muscles he needs to pull himself through at odd angles, and because he's really, ridiculously small. Eventually he grows too big to use the outflow vents anymore, but by then he [[spoiler:is the commander of Rabbit Army]] and so has access to the larger inflow vents.
* Works better in ''Literature/MrsFrisbyAndTheRatsOfNIMH'' than in most stories due to the escapees being rats. Well, right up until the system starts ventilating. This is one of the scenes that, legend has it, convinced Disney to pass it by as an animated adaptation. Something about having a large part of the party wiped out faster than the RedshirtArmy, and without even an enemy to credit for it. They need help in opening the grilles, too.
* Parodied in ''Literature/TheAdventuresOfSamuraiCat'', in which a cruise ship's air vents "... appear to have been ''designed'' for covert transportation." -- "That would explain the moving walkways and vending machines."
* Lyra crawls around in the dropped ceiling in Bolvangar in ''[[Literature/HisDarkMaterials Northern Lights]]''. Being a twelve-year-old girl, she's smaller and lighter than most {{Action Hero}}es, but she gets caught anyway, and almost transformed into a soulless abomination. She's only saved because the BigBad had a special interest in her, and was present.
* Used in the ''Literature/HonorHarrington'' spinoff ''Crown of Slaves'', but used more realistically than many examples. Crawling around in them is murderously hard work, characters without detailed schematics get badly lost, and it proves almost impossible to remove a grille without the proper tools. Additionally, the ducts in question are on a space station and are deliberately designed to be large enough to crawl through since they double as maintenance access passages.
* Referenced in Creator/TerryPratchett's ''[[Literature/JohnnyMaxwellTrilogy Only You Can Save Mankind]]'':
-->''"I saw a film where there was an alien crawling around inside a spaceship's air ducts and it could come out wherever it liked," said Johnny reproachfully.\\
"Doubtless it had a map," said the Captain.''
* Pratchett also pokes fun at the trope in ''Discworld/GoingPostal'' when, after a character fails to tunnel out of his jail cell, a guard remarks that the last guy in that cell -- who happened to be unusually small and nimble -- managed to squeeze through a tiny drain in the floor. Unfortunately, it didn't lead to the river like he thought.
-->"He was really ''upset'' when we fished him out!"
* Used and {{lampshade|Hanging}}d in Creator/JohnCWright's ''[[Literature/ChroniclesOfChaos Fugitives Of Chaos]]'', Vanity--who has the power to find-slash-create hidden passages--finds an accessible air vent.
* In Creator/SandyMitchell's ''Literature/CiaphasCain'' series:
** In ''Cain's Last Stand'', the air vents are exactly the place genestealers like to hide.
** In other books, following a close call in ''Death or Glory'', Cain makes a point of always acquiring the access codes to the maintenance conduits whenever he travels by ship. In one occasion where he didn't find the time to do so, Jurgen brought to his attention the fact that he was in a civilian ship, therefore its maintenance conduits didn't require access codes.
* Used in the last two books of Creator/TimothyZahn's ''Literature/{{Dragonback}}'' series; the (less-than-subtle) justification is that large air vents are actually standard design in capital ships, so that in the event of a hull breach emergency air supplies can be funneled to the compromised areas in large amounts, buying the occupants time to reach emergency air masks and so on. Although humans can't fit through them as it is, so it can almost be call a {{lampshad|eHanging}}ing. Shontine/K'da ships are actually ''designed'' for the stealthy, compressible K'da to be able to move through in case of hostile takeover, and a human sourly remarks that he outgrew the ability to navigate even big ships' navigation ducts when he was seven. When a K'da takes to those vents for the first time she gets thoroughly lost; in a later escapade she's almost caught when her tail twitches in shock enough to thump a vent.
** Played with in Zahn's Literature/{{Blackcollar}} novel ''The Backlash Mission'', where the air intakes for a huge underground military base are large enough an adult human can walk through them, in order to accommodate the massive inflow needed and the filtering equipment to keep out poison gas attacks. Since even with the vents camoflaged, this is an insanely large security risk, the intakes are designed with a very large kill zone of automated defenses, which are described as completely undefeatable and possibly viable for centuries without maintenance. [[spoiler: They actually were completely undefeatable. But with the base abandoned, there was no one to stop someone from spending months ''tunneling around'' the killbox.]]
* Slightly altered in ''Literature/HarryPotterAndTheChamberOfSecrets'', using the castle sewer-pipes for the monster to invade from -- and for the heroes to find -- the title chamber. Hogwarts Castle has got to have the most gigantic pipes ever seen... particularly for being built by wizards. [[spoiler: Somewhat justified, in that the pipe leading to the chamber was designed to be a passageway to it, and thus capable of being accessed by the Heir of Slytherin. Likewise, a massive snake would have much more success than other monsters in navigating plumbing. Both had been planned by one of the people who helped create the Castle in the first place.]]
* Comes up in several variations (breaking in, breaking out, air ducts, hanging ceilings...) in places in the ''Literature/VorkosiganSaga'' by Creator/LoisMcMasterBujold, particularly the short story "Labyrinth" -- where it involves problems like ducts forking or being blocked by grilles, and the others being only passable by the rather less than five-foot-tall main character, not his companions.
* In Creator/GrahamMcNeill's ''TabletopGame/{{Warhammer 40000}}'' novel ''Storm of Iron'', this is how Hawke escapes a launching rocket and a Chaos SpaceMarine.
* In the ''Literature/WomenOfTheOtherworld'' short story "Chaotic" in the anthology ''Dates From Hell'', Hope flees from a werewolf into an office, and finds herself in a dead end. She tries to escape through the air ducts, but she makes too much noise when moving and has to freeze when the werewolf enters the room. He finds her immediately. Later, after the pair has teamed up, they both move around through the air ducts, which are noisy, painful, cramped, and dusty. Still later, the bad guy enters a room looking for Hope, and while he's investigating the unscrewed air vent the good guys come out of their real hiding places and get the jump on him.
* Averted in Creator/RobertAHeinlein's ''Literature/RedPlanet'' when one of the good guys proposes taking a vent grille off of a wall to get to the room on the other side. His friend points out that there will certainly be a similar grille on the other side, fastened by screws they won't be able to reach.
* Creator/IsaacAsimov's ''Literature/LuckyStarrAndTheOceansOfVenus'': Bigman volunteers to use an air vent in order to access a critical relay which, once disconnected, will prevent the UnderwaterCity from drowning.
* Deconstructed in ''Literature/BlackDogs''. The ventilation in question is portrayed as tough, claustrophobic going in the dark, with Lyra, the protagonist, suffering several minor injuries, and a high chance of her falling and breaking her neck. Or breaking something else that renders her unable to escape, and dying slowly over several days.
* Subverted in the final book of the ''Literature/{{Sten}}'' Series, by having the hero nearly get stuck in a claustrophobic moment.
* Both played straight and subverted in Creator/JohnRingo's ''[[Literature/PaladinOfShadows Choosers of the Slain]]''. They need to sneak into the secure facility of one of the bad guys, so (played straight) they pick the slimmest girl on the team, as the men on the team are too large especially wearing all their weapons. Subverted because they knew she would get stuck half-way down when the air vents narrowed, so her sole job was to get to that point and release a small robot (an R2-D2 toy they had picked up in a toy store and then modified to include surveillance and communications gear) which could go the rest of the way.
* Used by Cammie and Macey in the third book of ''Literature/TheGallagherGirls'' series to get back into a building, though in this case it was still for escape rather than infiltration.
* Subverted and {{lampshade|Hanging}}d in ''[[Literature/StarTrekDeepSpaceNineRelaunch Star Trek: Section 31: Abyss]]''. After escaping her cell, Ezri Dax goes up into an air vent, which (contrary to what the holonovels of her youth would have her believe) is very dirty, dark, small and has creepy things living in it. (She is, however, successful in using the air vents to move throughout the base to important rooms.)
* Subverted in ''LightNovel/ACertainMagicalIndex''. In Volume 17 of the novels, Touma asks if he could use the ventilation ducts in the plane, but the flight attendant says that the ducts are too small. Touma admits that wasn't the plan and asks for some hot tea and coffee to pour down the duct, causing thermal expansion and make the terrorist on the other side ''think'' that there's someone crawling through the ducts, who lampshades that the act is just as suicidal as coming in through the actual entrance he was training his gun on. As a result, the terrorist gets some boiling hot tea to the face when he shoots the ducts, which also distracts him from Touma barrelling through the door and flinging a full pot of boiling coffee into his face.
* Used in ''Literature/AgeOfFire'', where the two dragon siblings escape from a raid on their home cave by escaping through naturally formed air passageways.
* In short story "[[http://www.baenebooks.com/chapters/0743471741/0743471741___3.htm In the Bone]]", the protagonist uses air ducts which were too small for his alien opponent but nonetheless navigable by the smaller human form. Some of the ducts are indeed too small for the human.
* Justified in ''Literature/WitchAndWizard''. In order to free innocent children being persecuted by the government for being witches and wizards from prison, the protagonist Wisty infiltrates one of the prisons through the air vents..... but she turns herself into a mouse first.
* Played with in ''Literature/TheVampireFiles''. Jack can justifiably play this straight if he assumes a gaseous form (gas, after all, being what air vents are ''designed'' to let through). However, he's a bit claustrophobic and can't shake the feeling of being trapped while traversing a ten-inch-square conduit.
* ''The Disreputable History of Frankie Landau Banks'' features the steam tunnel and pranking variant, as it is set at a school similar to MIT/Caltech mentioned above. It should be noted that this does not occur without consequences: one character gets a moderately-to-severe burn from the exposed pipes.
* Somewhat altered in ''[[Literature/The39Clues The 39 Clues: The Dead of Night]]'', in which Phoenix Wizard and Reagan Holt try to escape the Vespers' prison by climbing up a dumbwaiter shaft. Justified, since the characters are children.
* Averted and {{lampshade|Hanging}}d in Creator/SergeyLukyanenko's ''Literature/{{Competitors}}'', when Valentin and Lena are confined to quarters in a SpaceStation. When Valentin suggests escaping via the air vents, Lena laughs that he watches too many movies and points out that the vents are barely a foot wide. Valentin's suggestion to set off the fire alarm has Lena point out that this would cause the quarters to be depressurized to contain the fire.
* ''Under Alien Stars'' by Pamela F. Service has a crew from a hostile alien race take over a hotel, placing their prisoners on one floor. They remember to seal the edges of the air vents, but don't know or don't care about the garbage chutes descending past each floor.
* In Creator/MichaelFlynn's ''Literature/SpiralArm'' novel ''In The Lion's Mouth'', Bridget's first guess is such an escape before she deduces that in fact Ravn hid {{Invisibility Cloak}}s in the ventilation system, and then escaped, invisible, with her companion as soon as the door opened.
* ''[[Literature/TimeMachineSeries The Rings of Saturn]]'': The space pirate base has an extensive air ventilation system, extensive enough that a MadScientist was able to live alongside the inhabitants and move around the base for years without their knowledge.
* ''Literature/SixtyEightRooms'': The two kids manage to fit easily in the Museum's air vents as they have been [[IncredibleShrinkingMan shrunk down to five inches]]. Getting up to the vents was much harder.
* ''Literature/CannonFodder'': Kelsey says she escaped from Black Jack's base in this way, but we never see it happen.
* Attempted by Rolas in "[[Literature/TheRedVixenAdventures Captive of the Red Vixen]]", after he figures out that his ShockCollar is only tied to the door to his cell, but he finds a note from his captor and a trap waiting for him at the grille above the lifeboats.
* Averted in ''Literature/GetBlank'' when Blank uses a false ceiling, rather than any kind of duct, to get around.
* Occurs in ''Heaven's Queen'', third book of the ''Literature/ParadoxTrilogy''. When Brenton is helping Devi infiltrate Dark Star Station, he shows her a passage to crawl through and she assumes that it's an air vent. Brenton tells her that the people who built the station weren't that stupid; the passage is a power conduit, and usually filled with plasma heated to thousands of degrees. They're only able to use it as a passage because of a power outage.
* In ''Symbiont'', second book of the ''Literature/{{Parasitology}}'' series, Sally tries escaping captivity in a mall this way. She manages to make her way through the system only to find her guard Ronnie patiently waiting for her at the end; once he saw that she'd entered the vent, he was able to casually stroll over to the exit grating while she slowly crawled her way through the duct.
* In the ''Literature/DredChronicles'', the PrisonShip Perdition has enough of these that Tam, Dred's advisor, can use them to eavesdrop on rival gangs. This allows him to provide Dred with useful intelligence, which both protects the gang and encourages Dred to rely on him.
* Creator/AndreNorton's ''Literature/UnchartedStars''. While on the pirate space station Waystar, Murdoc Jern's companion Eet enters the station's air ducts to do some snooping.
* In ''Literature/TalesOfDunkAndEgg'', it's revealed at the end that [[spoiler: Bloodraven had a few dwarfs sneak in through the privy to steal the dragon egg. Justified, seeing as they're dwarfs]].
* In ''{{Literature/Wander}}'', Wander and Dagger use the airvents [[spoiler:to escape from a nest of smilers set up in an abandoned prison]].
* The main characters use this method of travel at one point in ''[[Literature/HIVESeries H.I.V.E.]]''. The trope is played a bit more realistically than usual: the vents are not well-lit, the characters are concerned about the noise they're making, their route has some difficult paths and "obstacles", and there's some mention of the effect that crawling along a cramped space would have. When entering the vents, they have to use a screwdriver to remove the grille. The only reason they don't get lost is because of Otto's uncanny ability to remember their route. However, they oddly don't have any difficulty removing the exit grille (and due to the exit's location, there was no way they could have checked it beforehand). There's also no excuse for the lack of security cameras in the air vents, given they're big enough to crawl through.
* ''The Boy Who Knew Too Much'' by Roderic Jeffries. A youth breaks into an abandoned factory on a bet and finds himself pursued by masked thugs. The detective assigned to the case is reluctant to believe him, but then sees the marks where the kid dived down a chute and notes that he must have been pretty scared to have jumped in there without knowing where it came out.
* Subverted in ''Literature/TheManyLivesOfStephenLeeds''. Ngozi proposes this as a way of getting into a building with security cameras -- because she's seen it on TV -- but J.C., who is a military expert (sort of), lists several reasons why it's impossible. They do find a creative use for an air vent, but it only involves hiding a mobile phone inside.
[[/folder]]

[[folder:Webcomics]]
* ''Webcomic/Angels2200'': Loser uses one when they attempt to "rescue" Quetz
* [[http://freefall.purrsia.com/ff800/fv00770.htm Subverted]] in ''Webcomic/{{Freefall}}'', when Sam finds out the hard way that the air ducts on his ship are not ''quite'' big enough for him to hide in. He might have succeeded if he had ditched [[StarfishAliens his encounter suit.]]
* Justified in ''Webcomic/SchlockMercenary'', as Schlock is a carbosilicate amorph -- he can squeeze through air vents no matter ''how'' small they are -- well, except for his eyes (standard SphereEyes) and his plasgun ([[HandCannon big]]).
* Justified in ''Webcomic/GunnerkriggCourt'', as the Enigmaron fortress that Antimony infiltrates is a [[HardLight simulation]].
* Used in a ''[[http://ubersoft.net/comic/hd/2007/11/secret-weapon Help Desk]]'' comic, the reasoning behind such large vents is questioned and explained as ContractualGenreBlindness in [[http://ubersoft.net/comic/hd/2007/11/bureaucracy-evil the next strip]].
* ''Webcomic/CaseyAndAndy''
** Subverted: Casey sneaks in through the airvents, but is met by [[EnemyMime the Mime Assassin]] inside the air vents, as the villain had been expecting the plan.
** The ''C&A'' villain Lord Milligan follows the Path of the Villain as a religion and deliberately follows every cliche. Including having giant air ducts.
** They try the air vent route multiple times, and the mime-assassin is in there every single time. Including the last time, when they were finally expecting it, and had someone outside the vent stab through it.
* Wonderfully subverted in [[http://cad-comic.com/comic/idiots-in-space-page-12/ a strip]] of ''Webcomic/CtrlAltDel'', given that it LEADS TO THE DEATH OF THE MAIN CHARACTER! Thus ending this {{Gamebook}} storyline.
* Nepeta is ordered by Equius to do this in ''Webcomic/{{Homestuck}}''.
** Later on, [[spoiler:Gamzee]] also does this to creep on others.
* Subverted in ''Webcomic/QuestionableContent'' when Raven attempts to enter Coffee of Doom through the airvent and gets stuck. She's not the [[TheDitz sharpest of minds]], though.
** And it's not like she was trying to rob the place or anything. She and another character, both recently hired there, show up to their opening shift and realize that neither of them have a key, on a day their boss is taking some personal time. Cue Raven's [[SarcasmMode exceedingly well-crafted plan]] to get in so they could open the shop without bothering said boss.
* In ''Webcomic/RoninGalaxy'', Taylor and Rin use the floor's ventilation ducts to [[http://www.roningalaxy.com/comic/page-78/ escape the brothel.]] They're both relatively small people, so it may be justified.
* ''Webcomic/SluggyFreelance''
** Used in [[http://www.sluggy.com/daily.php?date=011004 a strip]] to sneak into Aylee's office. {{Justified|Trope}} since Bun-Bun, a [[TalkingAnimal mini-lop rabbit]] is the only one who can make it through.
** Used again in [[http://www.sluggy.com/daily.php?date=001217 another strip]]. Also {{justified|Trope}}, since it's done by Rudolph the Reindeer, who has picked up all the tricks Santa uses for shimmying up and down chimneys.
* ''Webcomic/{{Banished}}'': To escape from the Boscis base, Rak and Timbo follow a Mammazon out this way.
* ''Webcomic/CharbyTheVampirate'': When Tony was cornered near a door he couldn't use inside the hunters' headquarters (since as an alp he can only leave the building the same way he entered it) he took possession of a rat monster to take the vents to where he needed to go.
* Justified in ''Webcomic/{{Curvy}}'' when used by a native of [[PlanetOfHats Candy World]] who is actually a ''liquorice''-based organism: she can squeeze into places a normal human wouldn't be able to. In fact, in the immediately previous page she's seen squeezing through the bars of a prison cell.
* Averted in ''Webcomic/DeadWinter''. Lou's plan for getting into the store for supplies involves this method, but Monday objects on the grounds that he won't fit. Apparently he's tried before.
* In ''Webcomic/{{Drowtales}}'', the air vents are too small for an adult Drow. But for a child...
* Trigger from ''Webcomic/FarOutThere'' is [[http://faroutthere.smackjeeves.com/comics/1067778/page-151-hey-at-least-its-not-all-going-to-waste/ very good at these]].
* In ''Webcomic/GirlGenius'' Castle Wulfenbach has a number of truly enormous grated vents which Gil uses to take Tarvek, Bang and Vole to one of his hidden labs when Tarvek figures out Gil's father has [[spoiler:been wasped]] and is somewhere on the ship covertly giving orders. Gil notes that Tarvek really needs to escape since even if he's wrong about what has happened to the Baron the Baron would likely have him shot on sight.
* In ''Webcomic/ElGoonishShive'', Noah uses air vents in the process of hunting a magical creature, and the trope is discussed in the commentary. And Noah also does it to ''get around school''! Raven has to shout at him to use the door.
* In ''Webcomic/TheMotleyTwo'', the spaceship "Hiroja" has vents big enough that the characters can sneak around the entire ship with impunity. Perria Makara, who snuck aboard undetected, even sleeps quite comfortably in the vents (near the heating unit).
* ''[[Webcomic/MetroidThirdDerivative Metroid: Third Derivative]]'': Samus with the Morph Ball up until [[TheCorruption Phazon corruption]] damaged her Varia Suit and required emergency repairs destroying the Morph Ball in the process.
* ''Webcomic/NerfNow'' on [[http://www.nerfnow.com/comic/735 air ducts in games vs. reality]]. No inescapable death trap is complete without one!
* {{Lampshade|Hanging}}d by the DeadpanSnarker in the improvisational comic ''The Omega Key'' on [[http://www.drunkduck.com/The_Omega_Key/index.php?p=229585 this page]], where he finds it suspiciously convenient that he (a ''6'10"'' man) can fit in an air duct. (He was right, as the destination turned out to be a trap.)
* In ''Webcomic/{{Outsider}}'', Jardin {{lampshade|Hanging}}s [[http://well-of-souls.com/outsider/outsider031.html the lack of handy vents.]]
* [[http://permanentinc.thecomicseries.com/comics/11 Malum Industries]] of PermanentInc have air ducts built [[InvokedTrope intentionally wide enough to crawl through]].
* While it would appear to be justified in ''Webcomic/StarMares'' due to ponies being smaller than humans (while the scale of the ships is unchanged from the originals, to better accommodate the larger ponies and pegasi), ventilation shafts are still explicitly stated to be designed for air, not ponies, and are depicted as being cramped and dirty. One character also later complains of the lack of security measures inside maintenance tunnels [[HypocriticalHumor (which she is in the process of sneaking through)]].
* In ''Webcomic/TheInexplicableAdventuresOfBob,'' this is how a quartet of [[http://bobadventures.comicgenesis.com/d/20120327.html time-displaced ninjas]] escape from the museum where they have awoken.
* Played with in ''Webcomic/BobAndGeorge'', where Kalinka and Ran try using air ducts to sneak ''into'' Wily's newest lair. Ran dies twice, trapping Kalinka in the duct, and necessitating that Blues show up to help her out of there.
[[/folder]]

[[folder:Western Animation]]
* ''WesternAnimation/{{Archer}}'' is fond of this. Somewhat surprisingly, it's always played straight.
* Subverted in ''WesternAnimation/AvatarTheLastAirbender''. The Gaang was stuck in a room and the only exits were air ''tubes'', so they tried to get Momo through it. However, Momo ate too much, and couldn't fit. Momo later ''did'' crawl through some tubes in Roku's Temple, though it wasn't actually an "escape".
* ''WesternAnimation/TheBatman''
** Justified when Ragdoll uses it; he is the most flexible person to have ever lived, and the air vent only needs to be big enough for his head to fit in, as many air vents are in RealLife.
** Also played straight in the episode "The Butler Did It" when Alfred has to escape from a room to warn Bruce. He pronounces it "quite a sticky wicket."
** And again in "Thunder" by Batgirl several times to escape from Zeus' henchmen on his airship, and to tinker with said ship's power supply.
* ''WesternAnimation/BatmanTheAnimatedSeries''
** In "The Cat and the Claw, part one", ComicBook/{{Catwoman}} uses the air vents to escape from the Multigon offices.
** In "Joker's Millions", Harley Quinn tries to escape from Arkham by going down the laundry chute. The guards ask WhoWouldBeStupidEnough to try one of TheOldestTricksInTheBook. AnswerCut to Harley whirling round and round in the laundry machine.
* Parodied and subverted in ''WesternAnimation/BatmanBeyond'': The protagonist enters a vent large enough to walk in, but the subsequent sections keep getting smaller and smaller.
* ''WesternAnimation/BatmanTheBraveAndTheBold''
** Subverted and played with: Batman is infiltrating a parallel Earth, disguised as his evil counterpart Owlman. He's allied himself with Red Hood, the heroic counterpart of the Joker, who is being tortured by Silver Cyclone, the evil version of Red Tornado. Batman sneaks through the air vents to free Red Hood and escape after his cover is blown by the evil Atom. This might have worked... ''except'' Silver Cyclone apparently had a tracking device or something on Batman, because the moment he realizes that Red Hood has been in contact with someone, he remembers that Owlman has been acting strangely and his computer immediately tells him Batman's location, in the air vents, proving that he's a spy. Silver Cyclone then powers up the fan to slice "Owlman" to pieces. This is the goddamn '''Batman''' we're talking about, so he blows up the fan. But still, the escape turned out to ''not'' be the best idea.
** Averted in "Menace of the Conqueror Cavemen!", as the air vents are cramped. They also shake and make a good deal of noise when Batman and Booster crawl through them. Fortunately Kru'll isn't paying much attention.
* ''WesternAnimation/Ben10'' did this a couple times, though it's {{Justified|Trope}} by the fact that, both times, Ben was transformed into an alien form that was five inches tall and gave him greatly enhanced brainpower.
* ''WesternAnimation/{{Birdman}}'' episode "The Quake Threat". When Birdman is trapped in an ElaborateUndergroundBase, Avenger the eagle breaks in through an air vent to save him.
* {{Lampshade|Hanging}}d and subverted in an episode of ''WesternAnimation/BuzzLightyearOfStarCommand'', when Emperor Zurg chews out the designer of his latest evil lair for making the air ducts big enough for heroes to fit through.
* ''WesternAnimation/ChipNDaleRescueRangers'' uses this in a few episodes. Then again, the use is probably justified as the Rescue Rangers themselves are only around 10 cm tall.
* ''WesternAnimation/CodeLyoko'':
** In the episode "End of Take", Ulrich and Sissi crawl through an air duct in the factory after being pursued by a prop alien. They don't get too far.
** In the episode "Canine Conundrum", Yumi and Ulrich escapes from the Gymnasium (besieged by robot dogs) this way. Although there is a joke, previously, about the adult teacher, Jim, being too fat to follow them.
* ''WesternAnimation/DannyPhantom'': In the episode "Doctor's Disorders", the only way to save the hero so he can stop the villain is to go ''in'' by the way of an air vent.
* ''WesternAnimation/TheDeep'': In "Lonesome Jim", Ant and Fontaine crawl through the air vents on EvilPoacher Conger's submersible base. Fontaine comments on how overrated air vents are as a means of passage.
* The ''ComicStrip/{{Dennis the Menace|UK}}'' cartoon does this in one episode when he's trying to flee with Gnasher from a large mobile mall that has arrived in [[ComicBook/TheBeano Beanotown]] and hypnotizing everyone into buying useless junk. Whilst crawling, they find the office of the mad scientist behind the plot, and instead of escaping Dennis decides to bring him down instead.
* In an episode of ''WesternAnimation/{{Detention}}'' Miss Kisskilya gets the gang in shape by locking up the school to lock them in the classroom, so they plot an escape through the air vent.
* This is Lee's usual mode of transportation around the school in ''WesternAnimation/{{Detentionaire}}''. He started doing it to keep out of Principal Barrage's way and off the security cameras, and by now has spent enough time in the vents to know his way around very well and be able to get from one end of the school to the other as fast by vent as he would using the hallways. Other characters have used air vents as well, though not to the same extent as the protagonist. The air vents of A. Nigma High also happen to house a red snake/lizard/dragon monster called a Tazelwurm, who could kill you in a second and is also the school mascot. [[spoiler:He turns out to not be as dangerous as he looks, though.]]
* ''WesternAnimation/{{Dogstar}}'': After Boombah locks the crew of the Valiant in their cabins in "Robbie", Simone has to crawl through the vents to reach the bridge.
* An earlier episode of ''WesternAnimation/EdEddNEddy'' about the trio trying to watch a monster movie marathon had them use this to get out of the bathroom and to the TV around Rolf(who was talking their ears off with another outlandish story). They do briefly get stuck, but Ed is able to push them out with relative ease.
* In the season 1 finale of ''WesternAnimation/ExoSquad'', after taking their attempt to use [[BigBad Phaeton]] as a hostage fails, [[TheSquad Able Squad]] escapes the Brood Chamber via the air ducts. Typhonus responds by sending troops into the tubes; why the tubes were made big enough for Neosapiens to walk around in isn't explained. Then he reroutes the ventilation so the tubes are flooded with poisonous "volcanic gas". Exactly why someone would build a ventilation system that allows that isn't explained either.
* Peter and Brian do this in an episode of ''WesternAnimation/FamilyGuy'', complete with a ShoutOut to ''Film/DieHard''. They don't make it all the way in stealthily, though; Peter's large girth causes the vent to give out and dump them right in the middle of the prom.
* ''Film/FantasticVoyage'' AnimatedAdaptation
** Episode "Revenge of the Spy". The protagonists use this technique to move around inside the enemy building, but it's {{justified|Trope}} because they're miniaturized to tiny size.
** Episode "The Perfect Crime". The criminals in their miniaturized helicopter use an air vent to attempt to escape the U.S. Mint building at the same time that the Voyager enters the building using another vent. The two flying craft meet inside the vent and do battle.
* In the made-for-TV WesternAnimation/FelixTheCat cartoon "A Museum, The Professor and Rock Bottom", [[DumbMuscle Rock Bottom]] tries to escape from Felix in the art museum by using this tactic. It doesn't work, because not only can Felix clearly hear him travelling through the air conditioning vent, the vent is so small that Felix [[TravelingPipeBulge can see Rock's burly form squeezing its way through]]. He forces Rock out by setting the temperature so low, that Rock slides out the vent, frozen solid in an ice cube.
* ''WesternAnimation/{{Futurama}}'':
** Subverted: Fry and Bender try to escape from a brig through a steam pipe vent. Unfortunately, the steam pipe is full of steam. At least they got a good sauna out of it.
** {{Lampshade|Hanging}}d in ''[[TheMovie Bender's Big Score]]''. While trying to destroy a [[Franchise/StarWars "Death Star"]], Al Gore's head in a jar flies a through an air vent actually ''labeled'' "Achilles' Vent", lasers a-blasting, successfully destroying it.
** In ''[[TheMovie Bender's Game]]'', Fry and the other travel around [[BigBad Mom's]] factory through a tube that sends chickens to the enslaved Nibblonians. It works, but they have to shove their way through a lot of chickens.
* ''WesternAnimation/GerryAndersonsNewCaptainScarlet''. Captain Scarlett tries this in "Proteus", but is instantly detected by sensors used to detect bacteria in the air vents. The MasterComputer then initiates a bacteria purge, so Scarlett has to blast a hole in the floor to escape.
* ''WesternAnimation/GravityFalls''. In the episode "The Inconveniencing", Dipper uses the HVAC vents to get into the abandoned Dusk 2 Dawn convenience store.
* Helga from ''WesternAnimation/HeyArnold'' used this method to sneak into the boarding house in "Helga Blabs it All".
* Given her size, Jade from ''WesternAnimation/JackieChanAdventures'' utilizes these at times to get around places when no one else can. The episode "The Day of the Dragon" feature both her and the Dark Hand using the air vents to escape Section 13.
* In a ''WesternAnimation/{{Jem}}'' episode, Jem, Aja, and Shana do this to escape a locked room.
* Subverted in the ''WesternAnimation/JimmyTwoShoes'' episode "Jimmy in the Big House", when [[IdiotHero Jimmy and Beezy]] tries to get out of prison by going through air vents. Suddenly, a screen pops out and it's a video message from [[EnfantTerrible Heloise]] who lets them know that they have made it far in escaping but in her prison, there is NO ESCAPE! As a result, they are blown out of the air vents by the fans at high speed and back to where they were. In this case, it's probably {{justified|Trope}} since Heloise probably made the vents that big just to [[ForTheEvulz crush prisoner's hopes for escaping]].
* ''WesternAnimation/JonnyQuest'' episode "Mystery of the Lizard Men". Jonny crawls though an air duct to escape from the title opponents.
* ''WesternAnimation/JusticeLeague''. In "Eclipse", Flash is being chased through the Watchtower by a possessed Superman. He does an AirVentEscape but [[FakeoutEscape leaves a door open to the corridor outside]]. Naturally Superman assumes Flash would rely on his SuperSpeed rather than [[BoringButPractical crawl slowly through the air ducts]].
* ''WesternAnimation/KimPossible'' and Ron infiltrated this way in TheMovie. They do it quite a lot during the series.
* Zadavia stages one on Deuce's ship during the ''WesternAnimation/LoonaticsUnleashed'' episode "In Search of Tweetums, Part II".
* In an episode of ''WesternAnimation/MaxSteel'', the only entrance to a highly-secured building is through the air vents. The only way in is by careful timing to avoid being sliced by a giant fan; the vents end two-thirds of the way up the wall in a room where the floor is littered with explosive devices, and not only do the air vents have cameras, they're also equipped with flamethrowers the big bad of the episode can activate at will.
* ''WesternAnimation/ThePenguinsOfMadagascar'': Penguins try this in "Officer X factor", but X switches the vent on and they fall down the passageway.
* Played straight in ''WesternAnimation/TheProblemSolverz'' episode "Badcat", when the solverz travel through a vent to reach Bad Cat's lair on the top floor of his casino.
* ''WesternAnimation/{{Recess}}'': T.J. often uses this route to break himself and occasionally others out of detention.
* ''WesternAnimation/RobotChicken'' {{lampshade|Hanging}}d this in an ''ComicBook/IronMan'' spoof. Two {{Mooks}} guarding The Mandarin's lair are able to instantly determine that the deafening banging and screeching noises they hear are from Iron Man trying to sneak through the air ducts.
* Sam and Max, and Sam's granny Ruth, try to reach the prison warden this way in the ''WesternAnimation/SamAndMaxFreelancePolice'' episode "Christmas, Bloody Christmas" -- only, instead of the air vent, they go through the prison's ''water duct'', and end up in the shower room.
* ''WesternAnimation/TheSimpsons''
** Parodied in the 100th episode. Santa's Little Helper gets into the school ventilation shafts, and only a greased Scotsman can catch him....
--->'''Groundskeeper Willie:''' Lunchlady Doris... 'ave ye got any grease?\\
'''Lunchlady Doris:''' Yes. Yes we do.\\
'''Groundskeeper Willie:''' ''[tears off his clothes]'' Then grease me up, woman!\\
'''Lunchlady Doris:''' ... Okee-dokee.\\
'''Groundskeeper Willie:''' There's nary an animal that can outrun a GREASED SCOTSMAN!
** This is how Homer spies on Mr. Burns meeting with terrorists, and would be caught if it wasn't PlayedForLaughs:
--->'''Homer:''' ''[scribbling on pad]'' I love spying.\\
''[terrorist picks up a bar of uranium; radioactive gas boils off the surface of the rod]''\\
'''Burns:''' Don't worry about those fumes. They'll be sucked into that air vent.\\
''[Homer moans from fumes, drops pad out of vent and onto the floor]''\\
'''Burns:''' This place is falling apart. ''[walks over, picks up pad and shoves it back into the vent]''
** In one of Homer's daydreams where terrorists take over the plant, Homer jumps from a standing position into a vent on the ceiling, then comes out in Burns' office to beat the terrorists up.
** In "Lard of the Dance", Bart and Homer crawl through the vents while trying to steal grease from the school cafeteria, followed by an angry Groundskeeper Willie. The passageway is wide enough that Homer and Willie can fight inside of it.
* In ''WesternAnimation/SonicSatAM'', most episodes that contain Robotropolis have the main characters in an air duct at LEAST once. Robotropolis is perhaps Air Duct Central, essentially one giant factory bathing in its own heated (polluted) air. Lots of cool (polluted) air has to be moved around to keep the place from overheating somehow. By the way, Robotnik hates this trope:
-->'''Robotnik:''' [[TranquilFury Tell me, Snively, how did the hedgehog get past all my security]]?\\
'''Snively:''' Through an air duct, Dr. Robotnik.\\
'''Robotnik:''' An ''air duct?'' Then SEAL IT OFF!!
* ''WesternAnimation/SpaceGhost'' episode "The Space Piranhas". Jan and Jace infiltrate an enemy base using the ventilation system. {{Lampshade|Hanging}}d when the BigBad says "As usual, the intruders have taken refuge in the ventilating system".
* ''WesternAnimation/SpiderManTheAnimatedSeries'' constantly had Spidey doing this. During the Venom arc, after Peter finds the symbiote and experiences drastic changes to his personality, he considers but chafes at using the trope, saying "That's the old Spidey talking." He instead goes for the direct approach: kicking the steel door down and barging into Kingpin's meeting.
* ''WesternAnimation/SpongeBobSquarePants'', "Truth or Square": after getting [[LockedInAFreezer locked inside the Krusty Krab freezer]], the gang makes their way out through the restaurant's labyrinthian ventilation system.
* ''WesternAnimation/StarWarsTheCloneWars'':
** [[Recap/StarWarsTheCloneWarsS1E5Rookies "Rookies"]]: During the initial commando droid attack on the Rishi Moon outpost, the titular rookie clones escape from the base via an airvent. The vent is used a second time as an exit when the clones are planning to blow up the base to cut off the hardwired all-clear signal and destroy the Separatist reinforcements.
** [[Recap/StarWarsTheCloneWarsS1E7DuelOfTheDroids "Duel of the Droids"]]: Ahsoka escapes General Grievous this way.
** "Cloak of Darkness": Ventress used the airvents to infiltrate and sabotage a Jedi Cruiser unnoticed.
** [[Recap/StarWarsTheCloneWarsS2E1HolocronHeist "Holocron Heist"]]: Cad Bane infiltrated the Jedi Temple through the airvents. Doubles as AbsurdlySpaciousSewer.
** [[Recap/StarWarsTheCloneWarsS2E8BrainInvaders "Brain Invaders"]]: Ahsoka Tano and Barriss Offee escape from mind-controlled clone troopers by jumping into the air vents. Later in the episode, Ahsoka uses the same vents to travel to the coolant control room and the bridge while she's running from Barriss.
** "Assassin": Aurra Sing used these to attempt to assassinate Padmé.
** Subverted and {{lampshade|Hanging}}d in [[Recap/StarWarsTheCloneWarsS3E18TheCitadel "The Citadel"]]. With the entry point the Jedi wanted to use blocked, Anakin and Obi-Wan muse how to get in, and Ahsoka points on the ventilation hatch. Anakin argues that they're too small to gain access, but in response Ahsoka points out, that they might be too small for Anakin, Obi-Wan and the clones, but she might be able to squeeze through -- which she is, although barely. In the next episode Obi-Wan's entire team tries to escape the Citadel in absurdly spacious airvents. However these had lethally effective security doors, and the warden at least had enough common sense to send at least one drone in the airvents.
** In [[Recap/StarWarsTheCloneWarsS5E7ATestOfStrength "A Test of Strength"]], Hondo Ohnaka proves he is smart by immediately recognizing the trick and having smoke bombs dropped into the vents to flush out the occupants.
** The second episode of the unfinished Utapau arc had Anakin and Obi-Wan try to escape from a group of armed weapons dealers by crawling through their ship's ventilation system. However, [[RealityEnsues not only do the arms dealers simply shoot into the vents, the vents are so cramped that the Jedi have to use the Force to move each other around to avoid getting shot.]]
--->'''Obi-Wan Kenobi:''' [[SarcasmMode Brilliant Idea.]] This is a much narrower space. No room to maneuver, we'll be shot for sure.\\
'''Anakin Skywalker:''' Sorry. [[DidntThinkThisThrough I thought it would be a good place to hide.]]\\
'''Obi-Wan Kenobi:''' It's ''never'' a good place to hide. [[LampshadeHanging We're always in the ventilation duct, every ship we go in.]]
* ''WesternAnimation/StarWarsRebels'': In the first two seasons, Ezra Bridger spends a ''lot'' of time crawling around in ducts. The fact that he's a scrawny, underfed teenager helps a great deal. By Season 3 he's had a growth spurt, [[RealityEnsues so he can't do this anymore]]. [[spoiler:Oddly enough, serves as a CallBack in the series finale, when Ezra decides to sacrifice himself he escapes the room through the air ducts, even noting "one last time" as he does.]]
* ''WesternAnimation/TeenTitans'':
** Exception; Titans Tower's quarantine lock-down system apparently ''does'' seal off openings to the air ducts, as seen in the episode "Haunted". (Robin got into the vents anyway....)
** Subverted in the same series: Cyborg is attempting an Air Vent Infiltration in the episode "Wavelength" when the walls roll up and the thing rotates, dumping him into an arena and a battle with Bumblebee which he very nearly loses. He should've thought twice about even coming across a vent ''big enough'' for his 6-foot, 200-pound chassis.
* This is a favorite route of the girls in ''WesternAnimation/TotallySpies'' for breaking in, clearly thanks to MaleGaze. Also done in the spinoff ''WesternAnimation/TheAmazingSpiez'' though vaguely more realistically due to the characters being 13 (Lee), 12 (Marc and Megan) and 11 (Tony). Even more plausibly the character seen doing this the most is Tony who, due to his young age, would realistically fit.
* ''Franchise/{{Transformers}}''
** ''WesternAnimation/TheTransformers'' episode "The Ultimate Doom, Part 2" introduced ventilation ducts large enough for Transformers to stand inside. Spike, Bumblebee & Brawn go through a ventilation shaft that takes them to Decepticon HQ. They're on Cybertron, where everything is of the same scale as Transformers are to humans, but why would they need air anyway?
** And pulled again in ''WesternAnimation/TransformersAnimated'', episode "Decepticon Air". Optimus Prime crawls through the ducts (it seems to be a squeeze, letting him homage ''Film/DieHard'' as well) of a spaceship -- maybe the air circulates to keep the energon from heating up and getting unstable? He does use it as a makeshift bomb, after all.
** ''WesternAnimation/BeastWars'': Cheetor goes through the ventilation shafts of the Predacon ship after having been accidentally transported to ''The Darksyde'' in "Equal Measures".
* The strangely clean air ducts of the SHIELD Helicarrier are {{lampshade|Hanging}}d in the ''WesternAnimation/UltimateSpiderMan'' episode "For Your Eye Only" which, as a spy movie parody with nods to ''Film/DieHard'', has Spidey using air ducts rather frequently.
* {{Defied|Trope}} in ''WesternAnimation/WolverineAndTheXMen'': Wolverine and Gambit are trying to break into a secret lab to steal back a power inhibitor collar, and Wolverine suggests taking advantage of this trope. Gambit counters with: "Heh, only in the world of cinema. [[ThisIsReality In real life, they never hold]]." It certainly doesn't help that Wolverine's metal skeleton makes him about three times as heavy as a normal person.
* ''WesternAnimation/XMenEvolution''
** Subverted, with the vent being only a few inches long, big enough for people to climb into, having a ladder inside, and Blob gets stuck. However, it also has a large amount of security lids which Cyke was able to close to keep Mystique from escaping.
** Played with in another episode. When the group is testing out the security of the mansion, Wolverine is able to go to many parts of the mansion through the vents, and suggests something be done about them.
* ''WesternAnimation/YoungJustice'':
** In "Homefront" - the DieHardOnAnX episode - Robin and Artemis spend a lot of time trying to avoid the Reds by crawling through the ducts; with varying degrees of success.
** In Season 2, a group of female team members do this in a bad guy's lair. The only one it makes sense for is Bumblebee who uses her shrinking powers to fit. On a more realistic note, all of the full-size heroines are shown having some difficulty maneuvering in the tight space.
[[/folder]]

* Wonderfully subverted in [[http://cad-comic.com/comic/idiots-in-space-page-12/ a strip]] of ''Webcomic/CtrlAltDel'', given that it LEADS TO THE DEATH OF THE MAIN CHARACTER! Thus ending this ChooseYourOwnAdventure storyline.