[[quoteright:303:http://static.tvtropes.org/pmwiki/pub/images/0000002163_20060919153745.jpg]]
[[caption-width-right:303:The Truth is out there. Trust no one.]]

->''I want to believe.''

'''''The X-Files''''' is an American [[LiveActionTV TV series]] that ran nine seasons (1993-2002) and two movies (''[[Film/TheXFilesFightTheFuture Fight the Future]]'', which was TheMovie, in 1998 and ''[[Film/TheXFilesIWantToBelieve I Want to Believe]]'' in 2008).

FBI Agent Dana Scully is assigned the task of keeping tabs on Fox Mulder, a talented FBI detective [[OccultDetective whose obsession with the paranormal]] is of great concern to his superiors. In particular, Mulder has become drawn to the "X-Files": a taboo collection of cold cases deemed unsolvable due to unexplainable elements. [[TheyFightCrime While Mulder attributes these elements to the supernatural and extraterrestrial, Scully is a sceptic who frequently attempts to debunk his theories through scientific reasoning]]. Together they investigate all manner of strange and unusual cases, [[MythArc which over time hint at a massive government conspiracy linked to a series of alien abductions in the Sixties]].

Creator Creator/ChrisCarter was celebrated for the show's innovative mix of cop-show conventions, paranormal phenomena, government conspiracies, action, wry humor and genuinely scary moments. In the mid to late '90s, the show's high production values and sharp writing helped it reach beyond the usual science-fiction genre fan base to make it one of the most popular and acclaimed shows on television and a bona fide worldwide cultural phenomenon. The show received a short-lived spinoff, ''Series/TheLoneGunmen''.

Although it genuinely was good in its own right, the series arrived at the right time for that to happen; mainstream interest in ufology and related topics peaked in around 1998. These days however, E.T. doesn't get quite as much airtime as he used to outside of fringe circles, and as a result, ''The X-Files'' as a series is a lot less culturally relevant now than it was during production.

Episodes alternate between standalone MonsterOfTheWeek episodes and a complex unfolding MythArc which deals with the government conspiracy and the various factions of aliens. A quarter to a third of the episodes of each season are part of the Myth Arc, including all season premieres and finales and most multi-part episodes. The final season was supposed to be followed by a series of movies that would eventually resolve the ongoing plot, but [[Film/TheXFilesIWantToBelieve the first post-series movie]] did not touch on the conspiracy plotline and met with lukewarm success.

The future of ''The X-Files'' and its Myth Arc remained uncertain for a long time while die-hard fans kept expecting a third film that would either close-up the mystery or revive the franchise. [[http://www.bleedingcool.com/2013/03/03/eccc-idw-panel-the-truth-is-still-out-there-x-files-chris-carter/ In March 2013, IDW announced that they're continuing the series as a comic book]]. The comic book marked as season 10 came out in July 2013 and picks up after the events of the second movie. And now it has a [[ComicBook/TheXFilesSeason10 trope page]]!

The show has a [[http://tvtropes.org/pmwiki/crowner.php/BestEpisode/TheXFiles Best Episode Crowner]] and many sub-pages like [[Characters/TheXFiles a character sheet]] or [[Recap/TheXFiles recaps]].

A webcomic [[http://www.shaenon.com/monsteroftheweek/?p=9 recapping all the episodes]] has been started by [[Webcomic/{{Narbonic}} Shaenon K. Garrity]].

----
!!''The X-Files'' and its MythArc provide examples of the following tropes:

[[foldercontrol]]

[[folder:A-G]]
* AbortedArc:
** At the end of the first movie, Scully talks about the vaccine that saved her, saying that it could cure people from the alien virus. It could also seriously mess up with the upcoming alien invasion. Sigh, the agents decided to pursue other things.
** During Season 6-7 the Syndicate was [[spoiler:destroyed at the hands of the Alien Rebels. At the time, the writers spoke of their plans for a new Syndicate, headed by Alex Krycek and Marita Covarrubias.]] This plotline was set up in "Requiem" but never resurfaced.
* AdventureTowns: The Dynamic Duo chases aliens, alien-human hybrids, clones, genetic mutants, vampires, serial killers or conspirators and encounters weird phenomena all over the United States. Plus in Norway, Hong Kong, Russia and Antarctica.
* AffectionateGestureToTheHead: Mulder and Scully would touch each other's forehead, stroke each other's hair, hold each other's head or cup each other's face. {{UST}} at its best.
* [[AgentMulder Agents Mulder]] [[AgentScully and Scully]]: The [[TropeNamer Trope Namers]] no less.
* AlienAbduction: A common theme, although it's usually ambiguous whether extraterrestrials or human conspirators are actually responsible for it. [[spoiler:Both Scully and Mulder]] were victims of it, among many others.
* AliensAreBastards: [[spoiler: The Greys fit this to a t. They didn't used to be like this, and were once very peaceful beings, but the Black Oil corrupted and twisted them like it does all other life.]]
* AlienAutopsy:
** Mulder acquires videotape of one such autopsy in "Nisei". Scully suspects it of being a fake, only it turns out that there's some truth to it.
** Mulder personally observes one in "Gethsemane". [[spoiler:However, an informant who worked for the Department of Defense claims that the subject of the autopsy was not a real alien but only what [[PowersThatBe "they"]] wanted Mulder to see.]]
* TheAllegedBoss: Walter Skinner is type 3. He eventually gets replaced due to his inability to make Mulder and Scully obey him. Alvin Kersh, the new boss, ''would'' be the same type, since it's not like Mulder, Scully and/or Dogget and Reyes listen to him any better, except for the fact that he plays dirty and has better connections within the Bureau than Skinner.
* AllTheoriesAreTrue
* AlternativeForeignThemeSong: The Japanese version has a few ending themes, including [[http://www.youtube.com/watch?v=iugHbSJ6ZMk "Love Phantom"]] by B'z, [[http://www.youtube.com/watch?v=IJOE-fCf6gw "Unbalanced"]] by Maki Oguro, and [[http://www.youtube.com/watch?v=5-3qSL19Yzs "True Navigation"]] by Two-Mix.
* AlwaysSaveTheGirl: In the very first episode, Mulder said that nothing else mattered to him except finding out the truth about the conspiracy and what happened to his sister. Early seasons of the show got a lot of mileage out of making him choose between pursuing his quest and saving Scully. Around the beginning of season 5, though, it pretty much ceased to even be an issue -- he decided Scully was priority #1 and never looked back. (She saves his butt just as often, of course.)
* AmbiguouslyGay: Phoebe in the episode FPS. She talks about feeling trapped by the testosterone around her, and refers to her female (and VERY attractive) video game creation as her 'Goddess.'
* AnchoredShip: For the first five seasons.
* AncientAstronauts: As explained in the MythArc and ''[[Film/TheXFilesFightTheFuture Fight the Future]]''.
* AnyoneCanDie: Starting with [[spoiler:Deep Throat]], and continuing throughout the rest of the show.
* ArbitrarySkepticism:
** Scully remains a hardcore skeptic long after she's seen shape-shifting aliens, watched Mulder be mind-controlled into [[NotHimself things he'd never do on his own]], etc. It's somewhat {{justified|Trope}}, though: later seasons tended to imply that Scully felt she had to take a more skeptical stance than she really believed anymore in order to keep Mulder's wacky ideas grounded.
** Even Mulder refused to believe in anything that was close to miracles and religiously paranormal stuff (in these episodes it's Scully who's open-minded, due to her religious beliefs). In episode "3", Mulder ''doesn't'' believe in vampires, that were real.
* ArcWords: "Trust no one", [[spoiler: Deep Throat's last words which come up various times throughout the series]].
* AscendedExtra:
** The Cigarette-Smoking Man had four brief, mostly wordless appearances in the first season, doing little beyond hover in the background smoking. His role gradually expanded, and by the middle of Season Two he was firmly established as the show's BigBad.
** There's Nicholas Lea, who parlayed a brief guest spot in Season One's "Genderbender" as a random character, before going into a major role as Alex Krycek in Season Two (a trope YouLookFamiliar). The character of Krycek is an ascended extra as he was originally conceived as a temporary partner for Mulder when Scully was missing, and the producers were going to kill him off if Lea didn't do a good enough job portraying him. He instead went on to appear in every subsequent season.
* BadassBookworm: An Oxford-educated psychologist and a forensic pathologist with a physics degree [[TheyFightCrime fight aliens (and all sorts of other things)]].
* BadassLongcoat: Worn by most characters who look rather intimidating. The FBI wear them, the conspirators wear them, the mysterious informants wear them, everybody wears them! They all wear long trench coats or lab coats, and they all look awesome in them.
* BadBlackBarf: An alien virus called "Black Oil" caused black liquid to come out of the mouth, nose and eyes of its victims.
* BadDreams: Mulder frequently has nightmares about his sister's abduction; it's probably the biggest reason he's an insomniac.
** Both Mulder and Scully have nightmares about the other during their separate abductions. For Scully, they come so often and regularly that she panics when she ''stops'' having them, fearing that Mulder's death is reason.
* TheBadGuyWins: [[spoiler:Well, the good guys don't, anyway. Sure, at the end of the finale CSM and Rohrer are both dead and Mulder has escaped. However, many of the conspirators are still alive, our heroes have been forced into a life on the run, they have just discovered the date of a planned alien invasion and are no closer to stopping the alien takeover than they were at the beginning of the pilot.]]
** Played straight in "[[spoiler:Sanguinarium]]", a MonsterOfTheWeek episode.
* BagOfHolding: Mulder's and Scully's pockets. Boy, do they have to be deep and spacious! They have there their FBI badges, mobile phones, wallet/purse, calling cards, coins, keys, pens, latex gloves, bags for collecting evidence, flash-lights of various sizes, and Mulder occasionally pulls sunflower seeds out of there.
* BandageWince: In the episode "Essence," Scully tends to a bad gash near Mulder's eye while he and Doggett sit at her kitchen table. They had gotten beaten up by Billy Myles, who had been recently revealed as an indestructible Super Soldier. Mulder winces and bats her hands away as she tries to clean the wound. Mulder teases her and tells her it's a good thing she gave up a career in medicine, since she has "manos de piedra" (hands of stone). Scully scoffs and swipes at his nose with a peroxide-soaked cotton ball. It's an adorable scene, if slightly awkward in that Doggett is sitting in the background being ignored while Mulder and Scully are...[[JustFriends being Mulder and Scully.]]
* BatSignal: Mulder summons his informants by switching on blue light lamp in his apartment (Deep Throat) and by putting the iconic X sign from masking tape on the window pane (Mr. X). Marita gave him his phone number, though.
* BeautifulDreamer: Used fairly frequently as a device for {{UST}} and to show how close and dedicated to each other Mulder and Scully are. When either of them was in the hospital, the other kept a vigil at the bedside. The following quote illustrating the trope is from "Redux II":
-->'''Mulder:''' I came by last night, but I... I didn't have the heart to wake you.
* BerserkButton: Do ''not'' come between Mulder and Scully. No, really. It's a ''bad'' idea. That goes for both of them, by the way.
* TheBigBoard: The X-Files office has bulletin boards and walls covered with pictures, photos and newspaper clippings concerning the paranormal and the cases Mulder and Scully were working on. In addition, they often used slide shows to present cases. Considering Mulder's interest in the paranormal and the level of his obsession, some might consider his office to be a RoomFullOfCrazy.
* BittersweetEnding: [[spoiler:At the end of the show, the GovernmentConspiracy has taken some hits but is still going strong, and alien colonization of Earth is supposedly inevitable and proceeding on schedule for 2012. Mulder and Scully are on the run from a death sentence... but they're both alive, and they're together, and that means maybe there's hope.]]
* BlackEyesOfEvil: They mean you've been infected with the Black Oil, some kind of alien [[TheVirus virus]]... thing.
* BlackHelicopter
* BlackSpeech: Whenever you hear German, Japanese or Russian, the chances are they are spoken by evil conspirators, and dark post-world-war-two and post-cold-war undertones are implied.
* BlandNameProduct: "Morley Cigarettes", the Cigarette Smoking Man's brand of choice -- although this isn't the first show on American TV to use Morleys.
* TheBlank: The Alien Rebels have no faces, having sealed every orifice on their bodies to prevent infection by the Black Oil.
* BloodyMurder: Alien-human hybrids with acidic blood.
* BodyHorror: All the time, especially in the MythArc episodes.
* BondVillainStupidity: The Conspiracy has opportunity to kill Mulder, but never does.
** Creator/HarlanEllison was complaining about this as early as the first season, apparently, leading to a scene where the Cigarette-Smoking Man explains that killing Mulder would "turn one man's religion into a crusade." (Which still comes across as sort of a HandWave, as they've killed plenty of dogged investigators before Mulder and TheConspiracy has remained intact.)
** In CSM's last appearance he claims [[spoiler:he protected Mulder from assassination [[EvilIsPetty so that he would learn The Truth that the alien invasion was coming, and there was nothing he could do to prevent it]].]]
* BookEnds
** "Requiem," which was written without knowing whether it would be the final episode, has a number of callbacks to the pilot episode. Mulder and Scully go back to Bellefleur, Oregon, which was the location of their very first assignment. They see a faded X sign on the road, which Mulder painted there to mark an anomalous electrical disturbance back then. They also meet some of the same people, some of which are multiple alien abductees. In both episodes, Mulder and Scully have a personal conversation in a hotel room -- in the pilot Mulder tells her "nothing else matters to [him]" except his quest, while in "Requiem," [[spoiler:he insists that the quest isn't worth sacrificing her health and happiness]].
** The series' actual finale, "The Truth," contains yet another hotel room chat, in which Mulder and Scully explicitly reminisce about the first one.
* BreatherEpisode: The comic relief episodes actually provided some of the more interesting and innovative {{filler}} and served to counterbalance some of the more ridiculous ''serious'' episodes as the series went on.
* CaliforniaDoubling: First the Vancouver version, then the show moved to California.
* CaptainsLog: Early seasons had Scully (and sometimes Mulder) writing case reports at the end of many of the MonsterOfTheWeek episodes. In the final seasons, after David Duchovny left the show, Scully read her journal entries as letters to the missing Mulder.
* ChekhovMIA: Mulder's sister. She did get used eventually. Or a [[spoiler:PosthumousCharacter]]?
* ChestBurster
* ChillyReception: Mulder toward Scully initially; later, either of them towards anyone replacing the other (especially between Scully and Fowley).
* ClockDiscrepancy: In the pilot episode Mulder & Scully get affected by a few minutes of MissingTime - there's a big bright light, and then the next thing they know it's 9 minutes later. Mulder marks the spot where it happened. Nothing comes of it at the time except to demonstrate Mulder's belief in the extranatural; but then in an episode [[BrickJoke years later]] it happens again and it turns out they're at the exact same spot.
* CloningBlues: First done in an early MonsterOfTheWeek episode with MythArc elements "Eve" and the trope keeps resurfacing in the mythology, e.g. "End Game", "Colony", "Herrenvolk" or "Memento Mori".
* CloningBodyParts: "Young at Heart" had a scientist ''trying'' to do this to prisoners (and removing the limbs from them so he could try to clone new ones) using salamander DNA mixed with human. You can probably guess how well this turned out.
* ConspiracyTheorist: Loads of 'em, including Mulder and the Lone Gunmen.
* ContagiousCassandraTruth: Mulder usually had this problem after convincing Scully. Other characters they convinced also tended to suffer this trope (if they weren't blackmailed or bribed by the AncientConspiracy).
* ContinuityLockout
* {{Contortionist}}: Eugene Victor Tooms, which doubles as CutLexLuthorACheck. As bendy and long lived as he is, he could have gotten along just fine selling tickets at the circus. But he had to use his talents to stalk, ambush and kill people.
* CoolOldGuy: Arthur Dales
* CreepyChild: Approximately one per season and several were a part of the MythArc stories.
* CrisisOfFaith: Scully started the show as a [[RaisedCatholic nonpracticing Catholic]]. Part of her CharacterArc involved her coming to terms with her faith and deciding she could pray and attend church regularly even if she didn't always agree with everything TheChurch said.
* CryptidEpisode: There are enough cryptid episodes to stuff the Berlin Zoo full with them.
* DarkerAndEdgier: Seasons 4 and 8.
* DeadlyDoctor: Evil doctors collaborate with the conspiracy, having no scruples performing experiments on people.
* DeadlyNosebleed: [[spoiler:She doesn't actually die of it, but]] this is the only visible symptom when [[spoiler:Scully]] has terminal cancer.
* DealWithTheDevil: [[spoiler:Skinner makes one with the Smoking Man to save Scully's life in season four. Mulder came close to doing the same, but ultimately didn't because he wouldn't have been able to face her afterward.]]
* DeathByPragmatism: [[spoiler:The Conspiracy]], despite their best wishes.
* DeclarationOfProtection: Mulder goes just a little nuts with the protection when Scully returns from being abducted in season two. He feels he failed to protect her from it, which is only compounded by the guilt he still feels over his sister's abduction years before. He ditches her when things get hairy, lies to her about where he's going so she won't follow him, and asks her to sit out cases for fear of her life. The only thing this does (besides piss Scully off--she's a trained FBI agent, after all) is show the bad guys that the only way to hurt him is to hurt her and it starts a vicious cycle of Scully being kidnapped, saved, and then Mulder being ''more'' protective.
* DeusAngstMachina: The main characters get a disproportionate number of metaphorical {{Groin Kick}}s just within the few years in which the show takes place. [[spoiler:Mulder has both parents die and is constantly tormented by people who appear to be his sister but aren't, but Scully takes the cake having one parent and her sister die (the sister being at least partly her fault) and the entire abduction plotline.]]
* DidTheyOrDidntThey: [[spoiler:Lots of teasing from late season seven on. Eventually it's confirmed that yes, they did.]]
* DiedHappilyEverAfter: [[spoiler:The fate of Samantha Mulder.]]
* DistressedDamsel / DistressedDude: One of the first shows to have both male and female leads carry the DistressBall more or less equally.
* DoNotAdjustYourSet
* ElectiveMute
* EmergingFromTheShadows: A common occurrence.
* TheEndOrIsIt: Leading to FridgeHorror galore. At the end of many episodes the things Mulder and Scully investigate are still running rampant and could be doing who knows what.
* EnemyMine
* EveryoneCanSeeIt
* EverythingsWorseWithBees: The GovernmentConspiracy uses bees as a vector for spreading TheVirus.
* ExploitedImmunity: In the episode "Nothing Important Happened Today" part 1. A female SuperSoldier who can't be killed lures a man into driving her home, forces his car to drive off a bridge and holds him underwater until he drowns.
* ExposedExtraterrestrials: Applies to most "Gray" aliens, except in the episode "The Unnatural," where [[ItMakesSenseInContext the Gray is wearing a baseball uniform]]
* ExpositionOfImmortality: Mulder and Scully run across a couple of long-lived characters during the series' lifetime; the first example is in "Squeeze," when Mulder is shown photos of Eugene Tooms that demonstrate he hasn't aged since 1933.
* EyelessFace: The alien rebels have their eyes, ears and mouth sealed up so they can't be infested with the 'black oil'.
* EyeScream: The alien rebels sewn up eyes definitely count. Creepy as hell!
* FacialDialogue: Mulder and Scully are ''very'' good at this. Most conversations have a layer of embedded subtext just from their facial expressions. It's also part of what makes the audience feel like they've walked in on something they shouldn't; it's very intimate.
* FailureIsTheOnlyOption: Goal: to expose The Truth.
* FakingTheDead: Mulder stages his suicide with Scully helping him to confirm the con in "Gethsemane"/"Redux" arc.
* FingertipDrugAnalysis: Mulder, ''all... the... time''.
* FirstNameBasis: Agent Doggett and Agent Reyes always call each other John and Monica, unless other agents are around. This likely comes from their time spent working together on the kidnapping and murder of Doggett's son years prior.
* FreshClue: A couple times, a still-burning [[BlandNameProduct Morley cigarette]] left on the ground or in an office ashtray indicates that the [[BigBad Cigarette-Smoking Man]] has been there recently. Since he's TheChessmaster who's far from careless, he most likely [[CallingCard deliberately left these there]].
* FriendOrIdolDecision: Mulder has to choose between saving Scully and finding Samantha and/or the truth about the GovernmentConspiracy several times over the course of the show -- most explicitly in "Endgame," but it also comes up more subtly in "Demons," "Redux," "Redux II," "The Sixth Extinction: Amor Fati" and "Requiem".
* FriendToAllChildren: For someone who was portrayed as the typical BigBrotherBully and who only had rare occasions to interact with children during the series, Mulder is quite good with them.
* GeekyTurnOn
** Mulder and Scully, many times:
-->'''Mulder:''' Looks like the fuselage of a plane.\\
'''Scully:''' It's a North-American P-51 Mustang.\\
'''Mulder:''' I just got very turned on.
** Or the one from "Chinga":
-->'''Mulder:''' Maybe you don't know what you're looking for.\\
'''Scully:''' Like evidence of conjury or the black arts, or shamanism, divination, wicca or any kind of pagan or neopagan practices. Charms, cards, familiars, bloodstones, or hex signs or any kind of ritual tableaux associated with the occult, santeria, voudoun, macumba, or any high or low magic.\\
'''Mulder:''' Scully?\\
'''Scully:''' Yes?\\
'''Mulder:''' Marry me.
** This one from "War of the Coprophages":
-->'''Scully:''' The very idea of intelligent alien life is not only astronomically improbable but, at its most basic level, downright anti-Darwinian.\\
'''Mulder:''' Scully... what are you wearing?
* GovernmentAgencyOfFiction: Much to everyone's chagrin and no one's surprise, there is no X-Files division of the FBI.
* GovernmentConspiracy
* TheGreys: Played a major role in the MythArc.
[[/folder]]

[[folder:H-M]]
* HalfHumanHybrid: Alien/Human hybrids.
* HeadbuttOfLove: Gently bumping their heads is Mulder and Scully's signature gesture of their mutual trust and support.
* HealingHands: Aliens have this ability, as well as several [[MonsterOfTheWeek monsters of the week]].
* HeldGaze: Mulder and Scully are big on doing this.
* HeroesWantRedheads: Mulder, obviously.
%% HeyItsThatGuy is trivia and go in the Trivia tab.
* HideYourPregnancy: Season 2 started to shoot as Anderson was pregnant. First was this (Scully is shot mostly seated, wearing jumpsuits, or in "unflattering angles"), then Scully got abducted just to avoid it. (Partly done because the character officially couldn't get pregnant.) (see WrittenInAbsence.)
* HollywoodHealing: Mulder, Scully and Skinner get shot and beaten up very badly many times but don't worry, neither of them has any nasty permanent scars whatsoever.
** The really horrible example is "Fight Club". Mulder's and Scully's faces are badly battered, bruised; they have stitches and Mulder's jaw is even wired, and his arm is broken. They are a sorry sight indeed, and they've beaten up one another! [[NotHimself Because of some half-sister doppelgängerish encounter]]. By the next episode, they're fine.
** Averted in "The Pine Bluff Variant" when Mulder gets tortured and in the next episode "Folie a Deux", his fingers are still bandaged.
** Also averted in "731": At the end of the episode Mulder's face bears very visible and believable marks from a severe beating.
* HollywoodSpelling: Constantly.
* HotScientist: Scully herself, Dr. Bambi Berenbaum the entomologist from "War of the Coprophages", Lisa Ianelli the cryobiologist from "Synchrony" and Susanne Modeski the troubled organic chemist from "Unusual Suspects" and "Three of a Kind".
* HowWeGotHere: Used several times for both MythArc and MonsterOfTheWeek episodes.
* HugeGuyTinyGirl: The show came up with the ScullyBox because David Duchovny is almost a foot taller than Gillian Anderson. In the few scenes that were shot without the box (or Scully in very high heels), Anderson barely reaches Duchovny's shoulder.
* IdiosyncraticEpisodeNaming: The MythArc episodes (often two-parters or trilogies) sometimes used complementary names as "The End"/"The Beginning", "Two Fathers"/"One Son", "Biogenesis"/"The Sixth Extinction I & II" or "Within"/"Without". The standalone episodes' titles were often extremely vague words or phrases brought up by a single line of dialogue or some other subtle or insignificant aspect of the episode, sometimes [[ForeignLanguageTitle in a foreign language]]. The show famously played a game with its fans who tried to find meaning in anything, no matter how obscure or insignificant it might appear, including the names of the episodes.
* IfJesusThenAliens: Averted. Scully is Catholic and believes in miracles, but is a hardcore skeptic about all other paranormal phenomena; Mulder is agnostic and rather cynical about organized religion but believes in basically everything else. (It's implied at least once that God is deliberately hiding himself from Mulder's perception as a test of Scully's faith.)
* ImprobableAimingSkills: Scully has them. Mulder...not so much.
* {{Jerkass}}:
** Agent Spender (though he had his sympathetic moments).
** Assistant Director Brad Follmer.
** Assistant Director Kersh is one [[spoiler:until the GrandFinale, where he helps break Mulder out of prison]].
* JerkassHasAPoint: One of the things that made Kersh a formidable antagonist towards Mulder and Scully was that he quite accurately pointed out that their actions often flaunted FBI procedure and law.
* JurisdictionFriction: Present in the very first episode.
* LampshadeHanging: Whenever an episode recycled a plot previously seen in another show or movie, someone would typically point it out.
** A particularly good one from the season six opener, when recapping what happened in ''[[Film/TheXFilesFightTheFuture Fight the Future]]'':
-->"Are you sure this isn't something I saw in ''Men in Black''?"
* LastNameBasis
** Mulder and Scully to each other. Mulder says he even made his parents call him Mulder, but it doesn't seem to have stuck. Mulder occasionally called Scully "Dana" [[YouCalledMeXItMustBeSerious at emotional moments]] in the first few seasons, then mostly gave it up, as if the last names had actually become more intimate by that point. Scully never even tried to call him Fox after the first time.
** The Lone Gunmen are also known only by their last names, likely because two of them have {{Embarrassing First Name}}s.
** Most of the agents at the FBI go by last names; Skinner is always called by his last name even after becoming more of a friend than a superior to Mulder and Scully.
** Averted by Reyes and Doggett, who refer to each other by first name on a regular basis.
* LeftHanging: An especially maddening example, since the show lasted nearly a decade -- it's not like they didn't have time to wrap things up.
* LetXBeTheUnknown
* LightIsNotGood: The classic "aliens have floodlights all over the place" effect.
* LighterAndSofter: Season 6, and most of the comedic episodes in general.
* LivingEmotionalCrutch: Both Mulder and Scully become this to each other, verging on HeroicBSOD whenever they're involuntarily separated. This is portrayed as basically a good thing; their relationship ends up helping both of them overcome their personal issues to some degree.
* LondonEnglandSyndrome: All over the place.
* LongingLook: Mulder and Scully had an astonishing talent for giving each other looks so singular, emotional and full of meaning they made anyone else in the room -- or on the other side of the television screen -- feel like they were intruding on some absurdly private moment.
* LongRunnerCastTurnover: By the time the series ended, only AD Skinner remained a main character. Mulder, Scully, and the Cigarette-Smoking Man were all demoted to regulars or extras.
* LovedINotHonorMore: Subverted. Several times the show puts Mulder in what looks like a FriendOrIdolDecision between saving Scully and his quest for the Truth -- but ultimately it's strongly implied that the only reason he's able to achieve any success in his quest is because he has Scully as his partner.
* TheManBehindTheMan
* MasculineGirlFeminineBoy: Mulder's emotional and intuitive, [[MenDontCry cries at least once or twice a season]], not all that good in a fistfight, has a habit of dropping his gun, and [[DistressedDude gets rescued by Scully]] at least as often as he rescues her. Scully's tough, logical, scientific, [[{{Kuudere}} rarely displays emotion openly]], [[ViolentlyProtectiveGirlfriend saves Mulder on a regular basis]], and has ImprobableAimingSkills. TheyFightCrime!
* MaybeEverAfter: [[spoiler:The television series ends on this note for Mulder and Scully.]]
* MeaningfulName: It's eventually revealed that the main alien antagonists call themselves the Purities. This should tell you everything you need to know about [[{{Narcissist}} what they think of themselves]]... not to mention what they think about ''[[OmnicidalManiac everybody else]]''.
* MedicalRapeAndImpregnate: It's strongly implied this happens to many victims of AlienAbduction. [[spoiler: Including Scully.]] Mulder actually calls the conspirators "medical rapists" at one point.
* MenDontCry: Averted. Mulder is much more prone to openly showing emotion than Scully is.
* TheMenInBlack
* MissingTime: Comes up several times, most prominently happening to Mulder and Scully in the very first episode.
* TheMole: A lot of these.
** Krycek, for all of one episode before he's found out.
** [[spoiler:Marita Covarrubias, X's replacement.]]
** [[spoiler:Fowley]]
** [[spoiler:Section Chief Blevins]].
** [[spoiler:Deep Throat]] is a Mole in the Syndicate.
** Mulder originally thought Scully was a mole (and says so outright when he first meets her).
* MonochromeApparition:
** In "Elegy", people reported seeing injured pale women trying to convey a message. It was found out that at those moments, the women were already killed and they were seeing their ghosts, all in pale blue colour.
** In "Tithonus", Alfred Fellig can recognize who is about to die. He sees the people going black and white when they are dying, while the background stays fully coloured.
* MonsterOfTheWeek
* MotherNatureFatherScience:
** Inverted. Mulder is the emotional, intuitive one who believes in mysticism and the paranormal, while Scully is a stoic, logical scientist. (The [[MasculineGirlFeminineBoy inversion of conventional gender roles]] was quite deliberate on the part of the writers.)
** Played jarringly straight in the few episodes where the MonsterOfTheWeek is a religious icon that Scully believes and Mulder doubts.
** Played straight in seasons 9 with Doggett and Reyes, as they were meant to replicate (but not duplicate) the believer/skeptic relationship of their predecessors.
** In season 8, with Doggett being the non-emotional, straight-laced former cop and Scully being the believer, it's played straight. Even though she's not as skeptical as she was when she joined the X-Files, Scully is still Scully. She's still the logical scientist, and though she admits she's seen things she can't ignore, she's ''not'' the believer. However, to keep the office running (and to keep Doggett from dismissing the work outright), she is forced to take on Mulder's role in his absence. In some of the episodes, you can tell she's suggesting things she absolutely does not believe in, but entertains them because the cases ''are'' X-Files. It's mentioned at least once that she finds it hard to "be Mulder," not only because she's never been the believer in the relationship, but because she is unable to make the insane leaps of logic Mulder was infamous for.
* TheMountainsOfIllinois: What happens when you film in Vancouver (and later Los Angeles) but set your stories all over the US, even the flat bits.
* TheMovie: Two of them. The first one is part of the show's MythArc, the second is basically a long MonsterOfTheWeek episode.
* MyBiologicalClockIsTicking: Scully's abduction left her infertile. It's a source of {{angst}} for her. It's played ''much'' more subtly -- and with good reason; he'd never be enough of a {{jerkass}} to actually bring it up, considering Scully's infertility -- but Mulder is implied to be somewhat wistful about not being in a position to have kids too.
* MysteriousInformant: Several. Deep Throat, X, and Marita are the three main recurring ones.
[[/folder]]

[[folder:N-T]]
* NoEnding: The series finale, "The Truth", [[NonIndicativeName does not actually reveal the truth]] or really resolve much of anything.
* NoHuggingNoKissing: The show was famous for this early on, but even then it was oddly subverted in a few instances, and by around season 6 Mulder and Scully had really become awfully, uh, cuddly for platonic friends.
* NoSenseOfPersonalSpace: Mulder in regards to Scully, as well as being quite affectionate. She is definitely unnerved by it in the early seasons, but eventually gets used to it.
* NotLoveInterest: While it took them seven seasons to get around to making it official, for all intents and purposes Mulder and Scully were best friends/lovers/spouses since day one. It could even be argued that their bond transcended all three of those roles to become something more all-encompassing than most people ever experience. It certainly cannot be ''denied'' that they were the most important people in each others' lives almost since the first time Scully walked into Mulder's basement office.
* NotOfThisEarth: The mysterious bacteria and virus, first appearing in "The Erlenmeyer Flask".
-->'''Dr. Carpenter:''' A fifth and sixth DNA nucleotide. A new base pair. Agent Scully, what are you looking at... it exists nowhere in nature. It would have to be, by definition... extraterrestrial.
* NotQuiteDead:
** Quite a few monsters of the week are shown to have survived their presumed deaths, from the flukeman in "The Host" to the rogue A.I. in "Ghost in the Machine", but very few of them ever show up again -- which makes one wonder [[WhatHappenedToTheMouse where exactly they went.]]
** Mulder on more than one occasion.
** Krycek, many times.
** The Cigarette-Smoking Man in season 5 and again in season 7.
** Jeffrey Spender, presumed dead in season six, but seen again in season nine.
* NoodleIncident: In season two, it's revealed that Scully has a key to Mulder's apartment. How this came about is never discussed. It's not known whether Mulder has a key to her apartment.
* ObstructiveBureaucrat: Practically everyone else in the FBI except for Skinner. In particular, Kersh and Follmer.
* OccultDetective: Mulder and Scully investigate the paranormal.
* OddCouple
* OmniscientCouncilOfVagueness: The mysterious and shady group called "Syndicate" effectively controls the world with various conspiracies.
* OneSteveLimit: Averted -- there are at least four fairly important characters named William, three of whom go by the nickname Bill: Mulder's father, Scully's father, Scully's older brother, and [[spoiler:Baby William]]. ''And'' it's Mulder's middle name.
* TheOnlyOneITrust: Mulder and Scully towards each other. No wonder they provide the page quote.
* OrificeInvasion: Very common, most memorably in the form of the Black Oil.
* OurHeroIsDead: Killing Mulder at the end of the season becomes almost traditional.
* OurMonstersAreDifferent: Well, most of the time.
* ParanormalInvestigation
* PlatonicLifePartners: Mulder and Scully [[spoiler:for the first five seasons]].
* PoliceAreUseless: Zigzagged. Mulder and Scully are themselves police and extremely competent, hence an aversion. Other cops, be they local police or other FBI agents, can be all over the place: genuinely helpful, well-meaning but ineffectual, obstructive bureaucrats or in cahoots with the Syndicate/Monster of the Week.
* PoliticallyIncorrectVillain: The Consortium as a whole. The upper levels seem to be composed entirely of older, upper-class white men. They also consistently failed to realize it was Mulder and Scully ''as partners'', not Mulder individually, who might pose a threat to their plans, thinking of Scully only as Mulder's BerserkButton when they could be bothered to notice her existence at all.
* PornStash: It's a recurring joke that Mulder has one. Unusually for the trope, he makes no real attempt to keep it secret, and Scully doesn't seem to care beyond thinking it's kind of silly.
-->'''Mulder:''' Whatever tape you found in that VCR? It isn't mine.\\
'''Scully:''' Don't worry, I put it in the drawer with all the other videos that aren't yours.
* PowerOfTrust: "Trust no one" is a major {{catch phrase}} in the show, but it's subtly ironic -- one of the show's main themes is actually the importance, in a world of lies and conspiracies, of having someone you can trust absolutely. Mulder and Scully spend so much time saying things like "You're the only one I trust," it became a common fandom joke that they were just using "trust" as a code word for "love".
* PowersThatBe
* ProperlyParanoid
* PurelyAestheticGlasses: Both Mulder and Scully are seen wearing reading glasses occasionally in the early seasons.
* ReassignedToAntarctica: Mulder in season 2 after the X-Files were shut down, and both Mulder and Scully in season 6 when Fowley and Spender replaced them.
* ReassignmentBackfire: Scully was pulled out of being a professor at Quantico to debunk Mulder's work on the X-Files. She is unable to do it and starts siding with him.
%% RecycledScript is trivia and go in the Trivia tab.
* RedemptionEqualsDeath
** [[spoiler:Agent Spender, who's killed by his own father, the Cigarette-Smoking Man, after handing the X-Files back to Mulder. Except that the last season episode "William" reveals that he didn't die. Instead, he was subjected to [[FateWorseThanDeath experiments that left him horribly disfigured]]]].
** Also [[spoiler:Fowley]].
** And [[spoiler:the Well-Manicured Man]].
* RedHerring: Red Herrings were used on the MythArc level as well in some standalone episodes. Several clues that appeared to be important to the mysteries the agents Mulder and Scully were supposed to unravel ultimately lead nowhere, or were not simply addressed again.
** The fate of Samantha Mulder was probably the biggest Red Herring of the series. Her abduction was a defining moment of Mulder's life as it triggered his belief in the paranormal and motivated his career at the FBI. Throughout the series, Mulder was tormented by her clones and reassurances that she's still alive. [[spoiler: However, it was revealed that she had been abducted by the conspiracy who had collaborated with the aliens. She was saved by some strange kind of fairies or angels which made her body disappear, meaning that her corpse will never be found, but Mulder did see her ghost.]]
** "Red Museum" is basically one big Red Herring. Viewers are teased by teenagers' weird kidnappings, the cult, a doctor's plane crash, cattle inoculation, or a peeping tom, but none bear significance for the resolution of the case. The episode appears to be a Monster of the Week story, but it turns out to be connected to the MythArc. However, those plots or characters did not resurface in the later mythology episodes.
* RelationshipReveal: [[spoiler:From late season 7 on it's hinted increasingly strongly that Mulder and Scully are already romantically involved. By [[Film/TheXFilesIWantToBelieve the second movie]] it's undeniable.]]
* RelationshipUpgrade: [[spoiler:Scully and Mulder]], but it happened offscreen and it's not clear exactly when. [[spoiler:The leading candidate is in season 7's "all things," which features Scully evaluating her past choices about life and relationships, leading up to a scene where she's getting dressed in Mulder's bathroom while he's asleep in bed, apparently naked.]]
* RewindReplayRepeat: Happens frequently, usually when Mulder catches a glimpse of something in the footage that everyone else overlooked.
* RoswellThatEndsWell
* SayMyName: The two leads do this an awful lot.
* ScienceHero: Both of them, but moreso Scully than Mulder.
* ScrewThisImOuttaHere: The Cigarette Smoking Man and Diana Fowley at the end of season 5.
* SelfParody: Most of the comedy-based episodes are this, with varying shades of {{Deconstruction}}.
** Probably at its most cutting and hilarious in ''Jose Chung's "From Outer Space"'', which takes near-constant jabs at the show's characters, narrative structure and MythArc (as well as Fox's AlienAutopsy video, [[BitingTheHandHumor for good measure]]) and ends with [[RefugeInAudacity Mulder in bed masturbating to the hoaxed Bigfoot video]].
--->'''Blaine''': One of them was disguised as a woman, but wasn't pulling it off. Like, her hair was red, but it was a little too red, y'know? And the other one, the tall, lanky one, his face was [[DullSurprise so blank and expressionless]]. He didn't even seem human. I think he was a mandroid.
* ShapeShifting: The Alien Bounty Hunters and several monsters of the week.
* ShipTease:
** A lot for Scully and Mulder, although they were mostly relatively restrained about it until around season 6.
** The writers were also very aware of other shippers in the fandom, including the [[SlashFic slash]] fans, and enjoyed throwing out occasional bones for the Scully×Skinner, Mulder×Skinner, and Mulder×Krycek crowds.
* ShoutOut: Enough with [[ShoutOut/TheXFiles it's own sub-page]]. And it's looong.
%% please list Shout Outs at the sub-page.
* SignatureItemClue: The ash from The Smoking Man's cigarettes have made it clear he's somehow involved a few times (one of the first being when it tipped Mulder off that he'd been in TheMole's car).
* SingleIssuePsychology: A lot of Mulder's issues go back to his younger sister's abduction while they were home alone together when he was 12. He actually calls Scully out for assuming everything he does is about his sister in "Oubliette," although in that episode she's entirely correct.
* SlidingScaleOfIdealismVersusCynicism: Pretty far over on the cynical side... but not quite as far as it might appear at first. It's [[CrapsackWorld a world of dark conspiracies, betrayal and lies, with monsters hiding in every shadow]], but there are two people in it who [[PowerOfTrust really can trust each other]], and that ''might'' [[EarnYourHappyEnding be enough]] to [[AWorldHalfFull make a difference]].
* SoundtrackDissonance: A favorite technique when coupled with the GoryDiscretionShot: something horrible would start to happen, and the camera would pan away, with cheerful incidental music being underscored by the sound of whatever godawful thing was happening. Used memorably in "Never Again" and "Home".
* SpiritualSuccessor
** To ''KolchakTheNightStalker''. Several ''X-Files'' episodes are directly inspired by ''Kolchak'' episodes.
** Has its own in ''Series/{{Fringe}}'', ''Series/{{Torchwood}}'', ''Series/{{Lost}}'', ''Series/{{Supernatural}}'' and several other ParanormalInvestigation programs. ''Fringe'' in particular so closely resembled ''X-Files'' that it was criticized by fans as being a ripoff of the original.
** It also influenced the mood and writing of less obviously related shows like ''Series/BuffyTheVampireSlayer'' (which Joss Whedon described as ''MySoCalledLife'' meets ''The X-Files''), ''Series/{{Alias}}'', ''Series/{{Bones}}'' and ''Series/EleventhHour''.
* StartToCorpse: Varies, but episodes frequently opened with unfortunate victims dying in mysterious ways, so it was often pretty close to zero.
* StatingTheSimpleSolution: The First Elder constantly suggests killing Mulder... only to be overruled by the other conspiracy members, who are either feeding him information or manipulating him for their own purposes.
* StrappedToAnOperatingTable
* StrictlyProfessionalRelationship: They started out purely professional but their relationship has been very strong since season 1, with several sweet bonding moments when they assured each other of their trust and loyalty. Every so often Mulder would flirt with a woman and not notice Scully's jealousy. Outside of that they were all business.
* SugarAndIcePersonality: Scully, as TheStoic, is very steely and distant with everyone, including her family. But with Mulder, she's a lot more relaxed and emotionally open.
* SuperSoldier: A new MythArc element added in season 9.
* SurveillanceAsThePlotDemands: Just assume the Conspiracy is always spying on everything.
* SuspiciouslySimilarSubstitute: Carefully and consistently averted.
** X was very different from Deep Throat, replacing grandfatherly benevolence with deadly pragmatism.
** Marita, X's replacement, was quite different from either of her predecessors and turned out to be a [[TheMole mole]] to boot.
** Doggett and Reyes were very different from Mulder and Scully, replacing the Absolute Believer/Healthy Skeptic dichotomy with Absolute Skeptic/Open-Minded, and replacing Mulder and Scully's MasculineGirlFeminineBoy with a more conventional gender dynamic. While they become close, they're never as [[LivingEmotionalCrutch emotionally dependent on each other]] as Mulder and Scully could be [[spoiler:even before they were romantically involved]], and they're on a FirstNameBasis right from the start.
* SympatheticMurderer: Very common. You're usually supposed to feel at least some degree of sympathy for the monster, even if Mulder and Scully end up having to kill it.
* ThereAreNoTherapists: Interestingly averted in the earlier seasons, at least for Scully. She sees a therapist a few times after her abduction in season two.
* ToBeContinued: They had several two-parters and trilogies. Some mythology stories ended with this as well, and the next episode would be a standalone one.
* ToiletHumour: Unfortunately. Mulder would often make not very tasteful jokes about hemorrhoids and similar things.
* TrademarkFavoriteFood: Mulder loves munching on sunflower seeds.
* TragicKeepsake: Scully always wears a small gold cross necklace. When she's [[AlienAbduction abducted]] near the beginning of season 2, it's torn off, and Mulder wears it himself for the three months she's missing. It shows up a few more times when they're separated as a symbol of their bond: Mulder finds it again when he's tracking down Scully in [[Film/TheXFilesFightTheFuture the first movie]], and [[TheLadysFavor she apparently gave it to him to wear before he went off alone]] and got himself [[PutOnABus abducted]] at the end of season 7.
* TrueLoveIsExceptional
* {{Tuckerization}}: Many character names, some of them are listed in the Shout Out sub-page. For starters, Mulder is the maiden name of Carter's mom, and Scully and Doggett [[NamedAfterSomebodyFamous come from Dodgers broadcasters Vin Scully and Jerry Doggett]].
* TurnCoat: It's a show about conspiracies, so there's lots of these.
[[/folder]]

[[folder:U-Z]]
* {{Ultraterrestrials}}: A key part of the MythArc -- [[spoiler:the "aliens" are actually Earth's original native inhabitants, who've returned from a leave of absence]].
* UndyingLoyalty: Mulder and Scully's loyalty to each other transcends time, space and apparent death, among other things.
* UnguidedLabTour: Comes up a couple times, though they usually aren't so much secret ''labs'' as academic or government labs doing secret ''things''.
* TheUnReveal
* UnresolvedSexualTension: Guess who? (The term actually originated in online ''X-Files'' fandom.)
* TheVirus
* VoluntaryShapeshifting: Various baddies, but the most prominent example is the Alien Bounty Hunter, a recurring antagonist. He's an extraterrestrial assassin, and can look like anyone.
* WasItReallyWorthIt: Various characters towards Mulder's quest, and Scully's involvement gets questioned as well. One of the most prominent cases is Bill Scully in "Redux II", accusing Mulder that it's his fault that he has lost one sister and is losing another, belittling Mulder and Scully's fight to reveal the truth and uncover the conspiracy as search for "little green men".
* WeaponizedOffspring: Flukeman would bite people and inject its parasitic larvae into them.
* WeHaveBeenResearchingPhlebotinumForYears: At various points throughout the MythArc.
* WellIntentionedExtremist: [[spoiler:The Syndicate.]]
* WhyDontYouJustShootHim: Even disregarding the rather questionable justification for the bad guys not simply offing Mulder as they've done with so many other people (that Mulder would become a martyr), they don't even seem to try to discredit him that much.
* WillTheyOrWontThey: [[spoiler:They will, and in the second movie they've been living together for six years.]]
* WhosYourDaddy: A major plot point in season 8.
* WorkingWithTheEx: When Diana Fowley comes on the scene at the end of season 5. The audience is never told exactly what went on between Diana and Mulder, beyond the fact that she was his partner on the X-Files before Scully and abruptly left him. It's heavily implied they were romantically involved, and it wavers between a NewOldFlame and OldFlameFizzle; Mulder is initially reluctant to work with her yet still trusts her, while Diana is eager to rekindle their past relationship. Neither of these things go over very well with Scully.
* WorldOfSnark: Everyone is a DeadpanSnarker, specially Mulder, Scully and Skinner.
* XMakesAnythingCool
** "The X-Files" sound way better than "the U-Files". They might have been called that for "unsolved" but weren't thanks to the filing system at the FBI in the 50's.
-->'''Clerk Bahnsen:''' It's in an X-file.\\
'''Agent Dales:''' An "X-file"?\\
'''Clerk Bahnsen:''' Yes, unsolved cases. I file them under "X".\\
'''Agent Dales:''' Why don't you file them under "U" for "unsolved"?\\
'''Clerk Bahnsen:''' That's what I did until I ran out of room. Plenty of room in the "X"s.
** Mr. X, Mulder's second MysteriousInformant.
[[/folder]]

!!Individual episodes provide examples of the following tropes:

[[folder:A-G]]
* AbnormalLimbRotationRange: Used as a plot point in "The Amazing Maleeni".
* AccentuateTheNegative: In "One Breath", when Melissa Scully calls Mulder out for doing this while trying to convince him to go to the hospital to see Dana, who is dying:
-->'''Melissa Scully:''' I don't have to be psychic to see that you're in a very dark place. Much darker than where my sister is. Willingly walking deeper into darkness cannot help her at all. Only the light...\\
'''Mulder:''' ''(disgustedly)'' Oh, enough! -- with the harmonic convergence crap, okay, you're not ''saying'' anything to me.\\
'''Melissa Scully:''' ''(angrily)'' Why don't you just [[SillyRabbitCynicismIsForLosers drop your cynicism and your paranoia and your defeat]]. You know, [[GoodIsNotDumb just because it's positive and good, doesn't mean it's silly or trite]]. Why is it so much easier for you to run around trying to get even than just expressing to her how you feel? I expect more from you. Dana expects more. Even if it doesn’t bring her back, at least she’ll know. And so will you.
* AdultFear:
** "Oubliette" features a child molester who kidnaps little pre-teen and teen girls and keeps them locked in a creepy basement. Amy, his latest victim, tried to escape but he caught her and dragged her back, and then denied her even water as punishment. She cried and begged him to let her go home to her mother. Finally, when he realized he couldn't have her, he tried to drown her in a river.
** "Home" was a very scary episode:
*** TheFamilyThatSlaysTogether might have been a bit exaggerated, but otherwise, such a nasty family of people who keep to themselves might exist. Abuse, incest, pain, filth, murder... For them, it represents their strength and unity.
*** There was a horribly deformed baby with every genetic defect imaginable. Agent Scully expressed her own uneasiness and anxiety over the issue.
---->''"Imagine all a woman's hopes and dreams for her child and then nature turns so cruel. What must a mother go through?"''
** The episode "Paper Hearts" featured a SerialKiller fascinated with ''Literature/AliceInWonderland'', fancying himself to be a Mad Hatter. He was a salesman and was very skilled in gaining people's trust. He took and murdered 16 little girls and kept [[CreepySouvenir twisted souvenirs]] in the form of hearts cut from their pajamas.
** "Sein und Zeit" had a Serial Killer who was taking children from their beds, but tormenting their parents and the police with notes about what he's done, which all end with "NOBODY MESSES WITH SANTA CLAUS!" He also made the parents themselves be suspected of the crime.
* AfraidOfBlood: "Blood"
* AgeWithoutYouth: "Tithonus"
* AIIsACrapshoot: "Ghost in the Machine", "Kill Switch" and "First-Person Shooter".
* AliceAllusion: In "Paper Hearts", Agent Mulder has to face again John Lee Roche, a convicted SerialKiller of little girls who was caught thanks to Mulder's [[TheProfiler psychological profile]]. He cut [[CreepySouvenir cloth hearts]] from his victims' clothes and kept them hidden in a copy of ''Literature/AliceInWonderland''. The phrase 'Mad Hat' appeared in Mulder's dreams and it was also a mark at a newly found crime scene. Roche used to live in Alice Road in Boston, and Mulder concludes that that's how he got the idea and that he took the role of the Hatter.
* AlienAutopsy: [[PlayingWithATrope Played With]] this one as well as made a ShoutOut to, and a TakeThat against, the TropeMaker in the episode "Jose Chung's ''From Outer Space''". According to AgentScully's [[RashomonStyle interpretation of events]], an autopsy which she performed on an alien and allowed to be video taped became commercially released as ''Dead Alien: Truth Or Humbug''. Embarrassed by it, Scully complains that the video ignores several of her findings, chief among them being that the dead alien was revealed to be a ManInARubberSuit.
* AllJustADream
** "Triangle". Possibly.
** [[spoiler:"The Sixth Extinction: Amor Fati".]]
* AlmightyJanitor: One episode only, but then he can take on different faces, which makes him pretty powerful as far as Janitors go.
* AloneWithThePsycho: Several times, but perhaps most frighteningly to Scully in "Irresistable" where the psycho is a non-paranormal SerialKiller.
* AnalProbing: Referenced and [[PlayingWithATrope Played With]] often. In "Jose Chung's ''From Outer Space''", for instance, it's Scully's opinion that a young couple whom [[AgentMulder Mulder]] believes were abducted by aliens were only engaging in sexual activity before they're old enough to handle it. Mulder, not seeing how this could discredit the girl's interpretation of events as revealed under hypnosis (which resembles the typical AlienAbduction story), asks his partner, "So what if they had sex?" to which Scully responds, "So we know it wasn't an alien that probed her."
* AnimatedTattoo: In "Never Again".
* AntiVillain:
** Preacher in "Sleepless".
** Gerry Schnauz in "Unruhe".
** The Cigarette Smoking Man, some of the time.
* ApocalypseAnarchy: In "War of Coprophages". People think that they are all going to be killed by cockroaches which got there either due to government conspiracy and their experiments, or that they are alien robotic invaders. Chaos ensues. It's most apparent in one scene in a convenience store where everybody is trying to grab whatever supplies they can and two ladies fight over the last can of insecticide.
* ArousedByTheirVoice: Chantal misses Mulder's sexy voice in "Small Potatoes". Considering that she's a phone sex operator, one must take it with a pinch of salt.
* ArsonMurderAndJaywalking:
** Conundrum from the episode "Humbug" eats anything: live animals, dead animals, rocks, light bulbs, corkscrews, battery cables, cranberries...
** In "Darkness Falls", Mulder's commenting a slide show and Scully asks about a photo of loggers.
-->'''Scully:''' Right, but what am I looking for?\\
'''Mulder:''' Anything strange, unexplainable, unlikely... boyfriend?
* AstralProjection: Rappo from "The Walk" can detach his phantom soul from his body.
* AtopAMountainOfCorpses: They [[PlayingWithATrope played with]] this trope twice.
** In "Teso Dos Bichos", a hoard of sewer killer pussy cats were filling an AbsurdlySpaciousSewer with dead bodies but the cats were not seen triumphantly sitting atop of them.
** In "Detour", Mulder and Scully fell into a pit full of dead and injured people that were dragged there by the monsters of the week. They tried to stack them so that they could get out of the pit.
* AuthorAvatar: In-universe example: the protagonist of the Cigarette-Smoking Man's rejected manuscripts, Jack Colquitt.
* AutopsySnackTime: Scully in "Bad Blood" examines the stomach contents and finds half-digested pizza appetising. Later she orders a pizza for dinner.
* AwayInAManger: Baby William's birth is this trope, though he's born in late May rather than December. This includes the proverbial StarOfBethlehem (which leads Mulder to the abandoned town where Scully gave birth) and the ThreeWiseMen as portrayed by the Lone Gunmen. An interesting birth, given that Mulder is a agnostic and Scully a Catholic--the symbolism probably wasn't missed by either of them.
* AwesomeMcCoolname: Pusher thinks that Frank Burst is the greatest name.
* AxCrazy
** Darren Peter Oswald in "D.P.O" -- it's safe to say that if you associate with him at all, you're putting yourself in ''serious'' peril.
** Cecil L'Ively enjoys setting people on fire.
%% ** Ellen Adderly
%% ** the transformed Ray Pearce also qualify.
* BackToFront: "Redrum" made use of this, but the central character was aware of it. He woke up in prison, not understanding how he got there. He goes to sleep that night, and wakes up the next morning to discover that he is going to trial, for the crime he was incarcerated for "yesterday".
* BeCarefulWhatYouWishFor: "Je Souhaite"
* BeforeMyTime: In "Travelers", Mulder goes to interview a retired FBI agent who investigated X-Files in TheFifties. The agent asks Mulder whether he's heard of the House Un-American Activities Committee, but immediately assumes that he hasn't. Even if he knew nothing about Mulder personally, the topic is covered in high school history classes.
* TheBermudaTriangle
** The episode "Triangle" sees Mulder investigate a [[GhostShip luxury passenger liner]] that mysteriously appears on the edge of the Bermuda Triangle. Once on board the ship, Mulder finds himself in the year 1939 as Nazi soldiers are fighting the British crew for control of the ship.
** In a later episode, {{Area 51}} [[TheMenInBlack Man in Black]] Morris Fletcher claimed to be the one who originally coined the term and insisted that powerful, primal, other-worldly forces are hidden beneath the waves, waiting to be plucked by man.
* BetterThanSex: In the episode "Jose Chung's ''From Outer Space''", when a Lt. Jack Schaefer is speaking to Agent Mulder, he says, "Have you ever flown a flying saucer? Afterwards, sex seems trite."
* BaitAndSwitchGunshot: In "Pine Bluff Variant", Mulder is about to be shot [[spoiler:but one of the terrorists is shot instead.]]
* TheBigBoard: The FBI are using a big chalk blackboard for a hostage negotiation in "Duane Barry".
* BitingTheHandHumor: In "Nisei", Scully dismisses an AlienAutopsyVideo as "even hokier than the one they aired on the Creator/{{FOX}} network".
* BlastOut: The opening to "Kill Switch". A rogue A.I. sends messages to several Washington D.C. drug dealers telling them that their arch rivals are meeting at this diner. All of them come and set up to wait. The final message is sent to a pair of U.S. Marshals, claiming that a fugitive is there, so they burst in to arrest him and cause a shootout. [[ThereIsNoKillLikeOverkill All to kill one nerdy guy in the middle booth.]]
* BlackBossLady: Sergeant Paula in ''X-Cops''.
* BlatantLies: In "731", a woman and her son walk in on Mulder standing over a dead man with his throat obviously slit. Mulder blithely passes it off as "he's just got a little motion sickness".
* BlessedWithSuck / CursedWithAwesome
** Tends to be the case whenever the MonsterOfTheWeek is human.
** In one episode, Mulder gains the ability to read minds. Too bad it's [[spoiler:basically making his brain melt]].
** Gibson Praise can also read minds, which leads to [[spoiler:pretty much all of the show's recurring bad guys trying to hunt him down and kill him]].
* BlondGuysAreEvil: Derwood Spinks in "Hungry" is a blackmailing ex-con who sadistically extorts the [[spoiler: AntiVillain, Rob Roberts]].
* BloodBath: In the episode "Sanguinarium", Nurse Waite is discovered lying in wait for Dr. Lloyd at his house, submerged in a bathtub filled with blood.
* ABloodyMess: Mulder did this in the third season episode "Revelations". The look on Scully's face was priceless before he explained that it was fake blood.
* BottleEpisode: Season 6 was getting expensive, so "How the Ghosts Stole Christmas" was one of these -- it takes place almost entirely in a single house and has only four cast members.
* BrickJoke: In the Season 1 episode "Beyond the Sea", Mulder gives Luther Lee Boggs a scrap of cloth. After Boggs makes a prediction about the victim based on the scrap, Mulder reveals he tore the fabric from his New York Knicks T-shirt. In the Season 3 episode "Clyde Bruckman's Final Repose", Mulder and Scully work with yet another psychic. The psychic (Clyde Bruckman) holds a similar scrap of fabric to his forehead. When Mulder and Scully are distracted for a moment, the psychic bursts out: "I got it! This is yours! This is from your New York Knicks T-shirt!"
* BriefAccentImitation: Gillian Anderson pulls out her British at the end of "Fire".
* BrownNote: In "Drive", a secret Navy communication device generates radio waves that vibrate at the same frequency as the human skull, inducing increasing intracranial pressure that literally blows the listener's brains out their ears unless the pressure is relieved surgically.
* BurialAtSea: Scully's father, a Navy captain, is cremated and buried this way in "Beyond the Sea".
* BuriedAlive: "Fresh Bones"
* BusmansHoliday: For Scully in the episode "Chinga". Ironic, since the very concept of the X-Files division was developed specifically to avoid a Busman's Holiday every week.
* ButYouWereThereAndYouAndYou: Said nearly word for word in "Triangle".
* CameraAbuse: In "War of the Coprophages", a cockroach crawls across the screen.
* CampGay: Steve and Edy from ''X-Cops''.
* CandlelitBath: Scully likes them.
* CasualDangerDialog: Mulder has a tendency to do this. "The Pine Bluff Variant" has one of the better examples, when Mulder is [[spoiler:undercover trying to infiltrate a domestic terrorist group]]. He's blindfolded, led into a warehouse, and has his hands strapped to a table.
-->'''Mulder:''' Is this the Pepsi Challenge? How ’bout some, uh, fresh air, boys?\\
'''Terrorist:''' Welcome, Agent Mulder... This is just a little method that we use to learn the truth.\\
'''Mulder:''' Well, you might want to put that hood back on me unless you want to see a grown man cry.
* CatsAreMean: "Teso Dos Bichos" had sewer killer cats.
* CATTrap: "Theef"
* ChosenConceptionPartner: Scully asks Mulder to be the father of her child in "Per Manum". In a heartwrenching twist on the trope, the IVF attempt fails.
* CliffhangerCopout: Near the end of "Gethsemane", the fourth season finale, the audience sees [[spoiler:Mulder alone in his apartment, crying with his gun in his hands. We cut away just before hearing his gun go off. The next scene is a flash forward in which Scully has apparently been called to his apartment to identify the body of a white male who died of a self-inflicted gunshot wound. She identifies it as Mulder.]] The next season begins by revealing that [[spoiler: Scully was lying, the body is not Mulder's, and the whole crying holding his gun thing was ''not related to anything''. (Specifically, Mulder probably was contemplating suicide -- until he was distracted by evidence that he was being spied on, confronted the spy, ended up shooting him, and concocted a plan with Scully to fake his own death.)]]
* CloseEnoughTimeline: "Dreamland". Everything gets set back to normal and the whole universe goes back to the way it was before the time rip -- but Mulder's apartment is still cleaned up and has a waterbed, and Scully still has a dime and penny that were fused together by the warp in space-time, even though the events that caused both scenarios ''never'' happened. It could be explained that they weren't in the path of the snap-back. A fan theory holds that the [[GroundhogDayLoop time loop]] in "Monday" later in the same season was triggered by the universe repairing itself and trying to get rid of Mulder's waterbed, the last remaining evidence of the paradox. This makes a surprising amount of sense when you watch the episode -- the starting point for each loop is the waterbed springing a leak.
* CombatStilettos:
** Scully wears them most of the time, sometimes even when she has no reason to be in work clothes and knew to expect trouble ahead of time.
** {{Lampshaded}} in the episode "Hollywood A.D.", when an actress portraying Scully in a movie (Tea Leoni, who happened to be David Duchovny's real life wife[[note]]until she got fed up with his chronic sex addiction, but that's neither here nor there[[/note]]) asks her how it's possible to run in heels that high.
** In "2Shy", she used them as a self-defense weapon by kicking a serial killer in the face.
** Ditto in "Leonard Betts".
* ComfortingComforter: At the end of "all things", Scully falls asleep on the couch while talking to Mulder. He pauses [[AffectionateGestureToTheHead to brush a lock of hair from her face]] and gaze at her before covering her with a blanket to be warm. A romantic example of the trope, since it's heavily implied they slept together for the first time later that night.
* CompellingVoice: Robert Modell, a.k.a. "Pusher".
* ContinuityNod
** A rather nice one in "Soft Light": A man has inexplicably disappeared from his hotel room. Mulder, Scully, and a young detective search the room for evidence of what might have happened. Having witnessed the events of "Squeeze" and "Tooms", Mulder and Scully naturally check out the heating vent. Cue the detective saying "You don't think anyone could ''squeeze'' through there, do you?" and Mulder quipping "You never know".
** There's a sweet FriendshipMoment in "The Field Where I Died" (an episode coincidentally about past lives).
-->'''Scully''': I wouldn't change a day. Well, except for that Flukeman thing. I could have lived without that just fine.
* ConverseWithTheUnconscious: In "One Breath," when Scully is returned after her abduction, Mulder is finally persuaded to go to her bedside and makes a sweet, awkward speech:
-->'''Mulder:''' I feel, Scully...that you believe...you're not ready to go. And you've always had the strength of your beliefs. I don't know if my being here will help...bring you back. But I'm here.
* CoordinatedClothes: In the second half of the episode "Eve", the murderous girls wear matching red hellish outfits. It was probably a case of IJustKnew or Eve 7 might have bought the outfits for them. Their identical looks make them even more disturbing.
* CorruptHick: The sheriff in the show's pilot.
* CouldntFindAPen: The opening episode of Season 4 has [[spoiler:X, Mulder's then-informant]] writing a message in blood on Mulder's doorstep, having been shot trying to bring information.
* CreepyCockroach: In "War of the Coprophages", cockroaches are the MonsterOfTheWeek, and at one point one scurries across the TV screen (as if it's [[TheFourthWallWillNotProtectYou IN YOUR HOUSE!]]).
* CreepySouvenir: Several times.
** "Squeeze": Eugene Victor Tooms took small personal things from his victims, e.g. a coffee mug, an ornamental snowstorm or a hairbrush. Mulder and Scully found this kitschy collection of trophies in his apartment.
** "Irresistible": Donnie Pfaster, a necrophiliac turned into a killer, had a hair and nail fetish. He took some fingers from dead bodies and also from the prostitute he killed. The FBI found a box in his freezer that contained [[BreadEggsMilkSquick ice, Brussels sprouts, some fingers, and a long fingernail, painted bright red]].
** "Our Town": The town of cannibals kept their victims heads in a cabinet. They were found at Mr Chaco's, but the whole town was guilty.
** "Paper Hearts": John Lee Roche was a serial killer who murdered sixteen little girls. He cut a piece of fabric in the shape of a heart from their clothes. He placed the cloth hearts in a copy of ''Literature/AliceInWonderland'' and kept the book in his car, thus being the 'carrying the trophies by himself' variety.
* CriminalMindGames: Mulder was the target in "Young at Heart", quite possibly "Grotesque", then "Pusher" and "Kitsunegari".
-->"A hunted Fox eventually dies."
* CrossOver: ''Series/{{Millennium}}'', ''TheLoneGunmen'', ''Series/{{Cops}}'', ''WesternAnimation/TheSimpsons'' and very possibly ''Series/HomicideLifeOnTheStreet''. Richard Belzer's appearance as Lieutenant JustForFun/JohnMunch on the episode "Unusual Suspects" is more of a [[TheCameo Cameo]] ShoutOut with a very direct {{Expy}}.
* CurseCutShort:
** "Bad Blood" - In the ColdOpen, Mulder chases down a vampire and drives a stake though his heart:
-->''(Scully shows Mulder his staking victim's very fake vampire teeth)''\\
'''Mulder:''' Oh sh-- ''(cut to opening credits)''
** Two examples in "Fight Club":
-->'''Mulder''' ''(on a cell phone)'' No [static] Sherlock.\\\
'''Mulder:''' ''(on a cell phone)'' Somebody's got to get to that fight and keep those two women apart or else this time the [static] is going to hit the fans.
** Mulder also does an "Oh, shi-" in "Triangle" when he realizes he's actually back in time; the camera pans away before he finishes.
** In "Jose Chung's ''From Outer Space''":
-->'''Scully:''' Well, of course, he didn't actually say "bleeped". He said...\\
'''Jose Chung:''' I'm, uh, familiar with, uh, Detective Manners'... "colorful" phraseology.
* TheDarknessGazesBack: The ending of "Detour". Luckily, [[spoiler:Scully]] left the room just in time.
* DatingServiceDisaster: "2Shy"
* ADayInTheLimelight:
** "Musings of a Cigarette-Smoking Man" shows him as a somewhat lonely man, [[MarriedToTheJob married to his job]] but [[HiddenDepths willing to give it up to be a writer]].
** "Unusual Suspects" does feature Mulder, but it's ''about'' and stars the Lone Gunmen. "Three of a Kind" is similarly about the Gunmen but has Scully around as a supporting character.
** "Avatar", "Zero Sum" and "S.R. 819" focus on Skinner.
* DeadlyBath: Both subverted ("Chinga" -- the music builds, we're sure something creepy's going to happen, the phone rings and... it's Mulder, he's bored) and played straight ("Squeeze", "Irresistible").
* DeadlyDoctor: In the MOTW episode "Sanguinarium".
* DeadMansHand: "Clyde Bruckman's Final Repose" has the title character playing poker with Agent Scully and holding a full house of aces and eights with the ace of hearts as the fifth card. As one might suspect from the episode name, he dies.
* DeathBySex: "Genderbender"
* DeathFakedForYou: "Young at Heart" had a false death certificate.
* DespairSpeech: CSM gets one that's [[BlackComedy played for laughs]] in "Musings of a Cigarette-Smoking Man".
* DestinationDefenestration:
** In the MythArc episdode "Erlenmayer Flask", one unfortunate man or hybrid was thrown out of a window and they tried to make it look like a suicide.
** It was also done in MonsterOfTheWeek episodes "Born Again" (defenestrated dirty cop) and in "Schizogeny" (a guy was pulled out of a room by trees).
* DisposableVagrant: Scully is informed in "731" about experiments performed on lepers, homeless and insane people. Quite interesting, actually, as they usually have no scruples about abducting anybody, not excluding their own family members or FBI agents.
* DoesThisRemindYouOfAnything: Scully getting a tattoo in "Never Again" is definitely played this way.
* TheDollEpisode: "Chinga", co-written by Creator/StephenKing and Chris Carter -- but still widely considered a pretty bad episode.
* DoomedHurtGuy: There are a few examples where Mulder and Scully go to great lengths to save someone, seem to succeed, only for the character to die anyway. Deputy Greer in "Agua Mala" is a notable one, whilst Gary Sacks bought the big one on Doggett's watch in "Alone".
* DoubleMeaningTitle: "Field [[MushroomSamba Trip]]"
* DramaticThunder: Taken to parodic extremes in "The Post-Modern Prometheus".
* DressesTheSame: Played with in "How the Ghosts Stole Christmas". The agents discover two decomposed corpses under the floor who have the same clothes as Mulder and Scully. It's of course one of the ghosts' tricks.
-->'''Scully''': Mulder, she's wearing my outfit.
-->'''Mulder''': How embarrassing!
* DrowningPit: In "Excelsis Dei".
* EatingTheEyeCandy:
** Eating the female eye candy happens in "First-Person Shooter" with the character of Jade Blue Afterglow. She was a very attractive stripper dancer dressed in a scanty silver miniskirt outfit. Every male character, including Mulder, has a major reaction towards her hotness.
** Eating the male eye candy occurs in "Bad Blood" when Scully met sheriff Hartwell. She was completely dazzled by his cowboy looks and cute smile.
* EccentricExterminator: In "War of the Coprophages", a cockroach exterminator opens the episode with a heartfelt ode to roaches before finishing it with "But to them, we humans are gods and should act accordingly" and stomping a particularly unlucky specimen on the floor. It doesn't end well for him.
* EldritchAbomination: The entity from ''X-Cops''. [[NothingIsScarier Never shown]], [[EmpathicShapeshifter takes the form of your mortal fear]], and utterly beyond physical reality. Mulder even describes it as a force rather than a physical entity, which makes sense considering that it kills one unfortunate nurse by becoming the ''hantavirus''.
* ElSpanishO: Mulder's hilarious "No-ho on the rojo" in "Little Green Men".
* ElvisLives: Mulder claims to believe this, but [[DeadpanSnarker knowing Mulder]] he could be making fun of himself.
* EmpathicEnvironment: In "Rain King", a weatherman's unrequited love for a local woman controls the weather.
* EnfantTerrible: The clones in "Eve".
* EngagingConversation: Mulder and Scully in "Small Potatoes" and "Chinga".
* ETGaveUsWiFi: In "Deep Throat", the experimental aircraft being tested by the military are theorized by Mulder to be [[ImportedAlienPhlebotinum reverse-engineered alien technology.]]
* EvenEvilHasStandards: In "Our Town", [[spoiler:Walter Chaco, responsible for the murder and cannibalism of at least 87 people, gives a heartfelt speech about how the town can't turn against its own members or they'd become "an abomination".]]
* EvilAlbino: "Teliko"
* EvilCripple: Several times, examples include the following episodes:
** "The Walk" has a quadruple amputee war veteran committing murders through astral projection.
** "Home" provides a hissing limbless mother of the incestuous Peacock clan.
** Subverted in "The Amazing Maleeni". The legless banker/magician in a wheelchair was faking it and he was not majorly bad.
** "Badlaa" presented a legless Indian BodySnatcher/illusionist.
* EvilElevator: "Ghost in the Machine" involves an elevator that is part of an office building's sentient computer network. It kills an investigator.
* EvilMatriarch: Mrs. Peacock in "Home".
* ExorcistHead: In "The Amazing Maleeni", the magician turns his head 360 degrees. It's speculated that he faked it [[spoiler: using his twin's head]] but it's never fully explained.
* {{Expy}}: Jose Chung is a double expy of Truman Capote and series adviser Jack Cohen.
* ExtremeOmnivore: The Conundrum ([[ActorAllusion played by The Enigma]]), in "Humbug".
* EyeScream. The show had several very squicky examples of this trope.
** It's mentioned in "Eve" where the insane Eve 6 says she bit a guard's eyeball, complete with clacking teeth for emphasis. She ''meant'' it as a sign of affection...
** In "Born Again", [[CreepyChild creepy girl]] Michelle keeps disfiguring therapy dolls in exactly the same way. She always gauges out one eye and cut one arm. This is how Charlie Morris's body was mutilated to make it look like a signature execution.
** "Die Hand die verletzt" features a human body with a heart and eyeballs cut out. Not coincidentally, Mrs Paddock's desk drawer contains a dissecting tray with a fresh and bloody human heart and two eyeballs.
** In the episode "Hell Money" about an Asian gambling ring, losers had to forfeit their own body parts for organ transplantation. We don't see the actual surgeries, but one of the men who was questioned had a fresh gauze-pad on his face, indicating that he'd just forfeited an eye.
** In "Unruhe", Gerry Schnauz gave several transorbital lobotomies to troubled women, believing that he was helping them. It used to be known as an icepick lobotomy and it involves inserting a leucotome through the eye sockets. Argh!
** The murderous doll in "Chinga" made people claw at their eyes in the teaser. Their faces near their eyes are horribly scratched and one poor guy didn't survive the attack: a knife ended up sticking out of his eye socket.
** "Theef" has a voodoo man who sticks two nails through a poppet's eyes that represents Scully which makes her eyes turn completely white and it effectively blinds her.
* {{Facepalm}}: Over its nine-year-long run, the show had several facepalms of various flavours.[[note]]"Am I the last sane person here?", "I can't believe ''I'' did something this stupid", "All right, what next..." or "I might break down completely every moment."[[/note]]
** "Syzygy": Mulder rubs his face with a hand when Detective Angela White comes to his motel room and he's not sure exactly what's going on.
** "Bad Blood": Scully facepalms when Mulder wants them to compare their accounts of one curious case that involved Mulder sticking a stake into a teen's chest. The facepalm followed his PrisonRape joke about Scully' hypothetical prison mate called Large Marge.
** "Patient X": Mulder is among panelists at a UFO conference. Other speakers take the abductions for granted and they enthusiastically talk about "the ontological shock" that must follow. Mulder is looking down, his hands are tightly joined and his thumbs are touching his nose bridge. He's deep in thought, trying to strengthen himself... because he's about to call it all bullshit and blame it on TheGovernment as their [[TheConspiracy their conspiracy]].
** "Je Souhaite": Scully puts her face in both her hands because she invited some scientists from Harvard to see an invisible body which unfortunately disappeared. She's beyond embarrassed.
** "The Truth": Agent Doggett tells Scully [[spoiler: that Mulder got death by lethal injection]], and understandably, Scully just loses it and heart-breaking sobs escape her uncontrollably. She covers her face with both her hands and continues to cry.
* FairyTaleMotifs: Always played very subtly, but they appear several times.
** There's [[spoiler:a DeusExMachina [[LittleRedRidingHood woodcutter]]]] at the end of "Schizogeny".
** [[Film/TheXFilesFightTheFuture The first movie]] has a subtle ''[[spoiler:Literature/SleepingBeauty and Literature/SnowWhite]]'' thing going on.
** "The Sixth Extinction: Amor Fati" has [[spoiler:Literature/TheSnowQueen]].
* TheFamilyThatSlaysTogether: The infamous episode "Home".
* FictionAsCoverUp: "Jose Chung's ''From Outer Space''".
* FieryCoverup: In the pilot episode, Mulder's motel room is burned to the ground to destroy evidence of alien abductions in Oregon.
* {{Fingore}}: Mulder gets tortured in "The Pine Bluff Variant".
* FistPump: Mulder pumps his both fists when he's confident that he figured out how to prove his theory in "Arcadia".
* FriendToPsychos: In "Mind's Eye", LiliTaylor plays a blind woman who has a one-way PsychicLink to a serial killer and cleans up his crime scenes after him.
* FreakyFridayFlip: "Dreamland", where Mulder and an Area 51 security officer get mind-switched.
* FullyAbsorbedFinale: "Millennium", for ''Series/{{Millennium}}'', and "Jump the Shark" for ''TheLoneGunmen''.
* FunnyBackgroundEvent: Scully teaching Tea Leoni how to run in high heels in ''Hollywood A.D.''.
* GasLeakCoverup: The episode "Jose Chung's ''From Outer Space''" features Jesse Ventura playing a [[TheMenInBlack Man in Black]] who tries to persuade someone who saw a UFO into questioning his vision and perception and believing he only saw "the planet Venus".
-->'''MIB 1:''' No other object has been misidentified as a flying saucer more often than '''[[LargeHam the planet Venus]]'''.\\
'''MIB 2:''' Even the former leader of your United States of America, James Earl Carter, Jr., thought he saw a UFO once, but it's been proven he only saw '''the planet Venus'''.\\
'''MIB 1:''' If you tell anyone that you saw anything other than '''[[RuleOfThree the planet Venus]]''', you're a dead man!
* GettingCrapPastTheRadar: The show practically turned this into an art form.
** A prime example:
-->'''Krycek:''' You're slipping, Mulder. I'm beating you with one arm.\\
'''Mulder:''' Isn't that what you do to yourself?
** Or from "The Ghost Who Stole Christmas":
-->'''The Ghost:''' I don't show my hole to just anyone.
** Carter wasn't allowed to refer to Donnie Pfaster as a necrophiliac, so the phrase "death fetishist" was used instead.
* AGlitchInTheMatrix: In "Kill Switch", Mulder realizes that his reality is not real when Scully saves him from evil nurses, but is not compassionate about his amputated limbs.
* GhostShip: Multiple instances.
** "Dod Kalm": Mulder and Scully get trapped in Norway on a boat. They age rapidly.
** "Triangle" has a ship from the past in Bermuda Triangle.
* GiveHimANormalLife: [[spoiler:Scully and Mulder eventually have a son -- and the aliens want to abduct him. They give him up for adoption to save him.]]
* GlamorousWartimeSinger: One appears in "Triangle".
* GloveSnap: Mulder accuses Scully of enjoying this. (It's in "Syzygy", an episode where [[WhenThePlanetsAlign planetary alignment]] was making everyone uncharacteristically cranky with each other. Or something.)
-->'''Mulder:''' Go ahead, I know [[DoubleEntendre how much you like snapping on the latex.]]
* GratuitousGerman: Frequently. Episode titles "Die Hand Die Verletzt", "Herrenvolk", "Unruhe" and "Sein Und Zeit"? An entire episode ("Unruhe") centered around a German-speaking serial killer (in which Scully herself speaks German)? ThoseWackyNazis in "Triangle"?
* GreenAesop: A few times, notably in "Fearful Symmetry," which won an Environmental Media Award.
* GroundhogDayLoop: Episode "Monday". The time loop begins on Monday morning when Mulder oversleeps and has to deal with a leaking waterbed, and ends with an exploding bank with Mulder and Scully inside. Only one woman is aware of the fact that the time repeats itself constantly.
* GunmanWithThreeNames: Averted as they are not lone gunmen, but serial killers: Eugene Victor Tooms, Luther Lee Boggs, John Irvin Barnett, Warren James Dupre, Donald Addie Pfaster, Darin Peter Oswald, Robert Patrick Modell, John Lee Roche, and Wilson Pinker Rawls.
* TheGrotesque: The Great Mutato from "The Post-Modern Prometheus".
[[/folder]]

[[folder:H-M]]
* HandsOnApproach: Mulder teaching Scully to play baseball in "The Unnatural".
* HauntedTechnology: They loved this trope, though the technology wasn't usually haunted so much as just plain evil. Sometimes it was subverted at the end by implying that there was somebody controlling the device all along.
** "Ghost in the Machine" is about an automated security system that develops a murderous mind of its own.
** "Blood" has machines telling people to kill. Subverted - perhaps it was the government, using chemicals to cause mass paranoia in a controlled experiment and perhaps some people were actually sending the messages.
** "Wetwired" explores a device planted in a TV set sending subliminal signals and inciting the worst fears in viewers. A subversion since it's clear that TheConspiracy placed it there.
** "Unruhe" features photography that can capture what's inside people's mind.
** "Kill Switch" is similar to "Ghost in the Machine". It's about a software that goes rogue and tries to kill anyone who tries to destroy it. The only way to deactivate it is to insert the kill switch which plays to the tune of The Platter's "Twilight Time".
** "First-Person Shooter" has a female video game character in a realistic 3-D game that starts killing people in the game - with effects in real life.
* HallOfMirrors: "Humbug"
* HatePlague: "Ice", "Syzygy", "Red Museum", "Wetwired" and "Fight Club".
* {{Headdesk}}: Daryl Mootz in "Rain King" bangs his head on the desk when he hears the sum he's being sued for.
* HemoErotic: "3" features the sexy vampire Kristen Kilar who licks her own blood and blood of other people. She has some sexually explicit scenes, including the one where she is shaving shirtless Mulder.
* HeroicFireRescue: Episode "Fire" has two examples. Cecil L'ively successfully attempted to invoke this trope by setting the fire at the hotel so that he could save the boys. It was then played straight with Agent Mulder who rescued the children from the burning house at the final showdown, having to face his paralysing fear of fire.
* HeroStoleMyBike: In "Drive", Mulder is forced to borrow an old station wagon. Unusually for the trope, AD Kersh chews him out later for it.
-->'''AD Kersh:''' Compensation to one Walter R. Duncan for unauthorized use of his 1968 Caprice station wagon: $500.
%% HeyItsThatGuy is trivia and go in the Trivia tab.
* HighDiveEscape: Agent Mulder dives off the ''Queen Anne'' [[NowOrNeverKiss after kissing Scully]] in "Triangle", a TwoFistedTales pastiche.
* HistoricalInJoke: CSM takes credit for both the 1980 "Miracle on Ice" and the Bills' run of SuperBowl failures. During a meeting, he's told that [[UsefulNotes/GulfWar Saddam Hussein]] is on the phone; he says he'll call him back later. (Note that this is in one of the UnreliableNarrator episodes, though.)
* HoldingHands: Mulder and Scully do this as a gesture of solidarity and support, notably in "Little Green Men", "One Breath", "Pusher", and the 1998 movie ''[[Film/TheXFilesFightTheFuture Fight the Future]]''.
* HollywoodSatanism: The crimes in the episodes "Syzygy" are believed to be the committed by the satanists.
* HollywoodVoodoo: "Fresh Bones"
* {{Homage}}: "The Post-Modern Prometheus" is an homage to old monster movies, especially ''{{Frankenstein}}''. It is filmed in black and white and comes complete with a [[LargeHam hammy]] MadScientist, a gentle monster, and [[DramaticThunder thunder and lightning whenever somebody says something dramatic.]]
* HorrorHunger: "Hungry"
* HumanoidAbomination
** Greg Pincus
** Phyllis Paddock is revealed to be one as well.
* ICannotSelfTerminate
** An immortal man tired of life from "Tithonus" who tried pills, cutting his wrists or jumping several times.
** Victims from "The Walk" were unable to kill themselves as the villain of the week wanted them to suffer and he used his psychic powers to prevent them from committing the suicide.
* IdiotBall: Scully grips onto Idiot Ball pretty tightly in "Dreamland". Recap: Mulder and Morris Fletcher (a man-in-black played by Michael [=McKean=]) have switched bodies due to a UFO passing overhead. Fake-Mulder is pretty happy about this and makes no effort to rectify the situation, and behaves ''very'' oddly by Mulder's standards on returning to work, driving Scully up the wall to the point she suggests there's something seriously wrong with him. When Real-Mulder finally manages to talk to her, explain, and relay a load of details about her only he could know, and despite pretty much '''the exact same thing happening a season and a half earlier''' ("Small Potatoes"), what does Scully do? Disbelieve him and calls the authorities on him.
--->'''Mulder:''' Look, your full name is Dana Katherine Scully. Your badge number is... hell, I don't know your badge number. Your mother's name is Margaret, your brother's name is Bill. He's in the Navy and he hates me. Lately you've been having for lunch, I dunno, this six ounce cup of yogurt, plain yogurt into which you stir some bee pollen because you're on some kind of bee pollen kick, even though I tell you you're a scientist and you really should know better.\\
'''Scully:''' That information could've been gathered by anybody.\\
'''Mulder:''' ''[gives her A Look]'' ....even that yogurt thing? That's so you. That's so Scully. The fact that ''you'' haven't changed is still somewhat comforting.
* IKnowYoureInThereSomewhereFight: Mulder tries this in "Schizogeny" when the villain is finally revealed, [[spoiler:only for the Orchard Man to chop her head off.]]
* ImpossiblyAwesomeMagicTrick: In "The Amazing Maleeni", the stage magician Maleeni has a magic trick where he rotates his head 360 degrees. Every other trick performed in the episode is possible in real life.
* ImprobablyHighIQ: Mostly an inversion of an ImprobablyLowIQ, in the episode Roland, the title character is portrayed as someone with at least moderate disabilities (eg, can't operate door opening system, limited speech capabilities, passing the time in his group home with young child activities such as stickers), but is said by Scully to have an IQ of slightly above 70, which is in the borderline category like Forrest Gump, and he usually should be indestinguishable in everyday situations from everyone else. It is suggest that he has autism which could account for some of these factors as well as his head rolling, (though he doesn't have most autistic tendencies like problems with eye-contact), but the well-known tendency is for IQ tests to significantly ''underestimated'' IQ in people with autism.
* INeverToldYouMyName: On one episode, a character gives himself away with this trope but he's talking so fast that the audience might not notice until Mulder stops him, saying, "Whoa, whoa, wait a minute here... When did I say my name was 'Agent Mulder'?"
* InfantImmortality
** Averted in "The Calusari", "The Walk," and "Home". Also the dog exmaples from "Quagmire" and "Teso Dos Bichos".
** Played straight with Baby William, though, at every turn. The number of times that child should have died, before and after birth, are staggering. But not even a scratch.
* InNameOnly: While not as bad as most cases, the Jersey Devil featured in an early episode is barely anything like the cryptid that's actually reported. It's basically twisted into a poor-man's Bigfoot and dosen't show any of the actual urban myth's notable aspects other than living in the Pine Barrens in New Jersey and the name.
* InsaneEqualsViolent
** "Grotesque" has a SerialKiller who claims that he's possessed by some dark spirit. Scully thinks he suffers from a dissociative disorder and Mulder informs us that he spent the better part of his twenties in an insane asylum. The episode deals with the issue of spirit possession versus insanity.
** In "Chimera", the monster-of-the-week is revealed to have got some kind of dissociative multiple personality disorder: split personality. The woman's overt self was not aware that it was her who was committing the murders.
* TheIsomniac: Mulder
* IntimateHealing: Mentioned in "Detour". If only it had rained sleeping bags...
* IntoxicationEnsues: Accidental use of substances causing altered and loopy behaviour. The drugs might be administered maliciously. Done several times.
** In "Anasazi", the conspirators have been drugging water in Mulder's building to make him irrational and violent. There was a murder due to the drugs.
** "Never Again": Ed Jerse's tattoo of a seductive girl named Betty talks to him and forces him to do horrible things. It's revealed that the red tattoo ink was made from rye and contained ergot alkaloid that causes aural and visual hallucinations. Scully got a tattoo as well, but was not affected to that extent.
** The vampire from "Bad Blood" drugged Mulder's pizza. He [[RashomonStyle did or did not]] sing the theme from ''Film/{{Shaft}}''.
** In "Three of a Kind", Scully is injected with a brainwashing drug to make her forget some evidence she's uncovered, one of its side-effects being the inhibition of higher reasoning. We later see her enthusiastically flirting with an all-male group of defence contractors and TheMenInBlack. Fortunately, Frohike takes her away, much to their disappointment.
--> '''Frohike''': Why would the government want to turn Scully into a bimbo?
* InverseLawOfFertility: Inverted -- [[spoiler:Scully doesn't seem particularly interested in having kids until she finds out her abduction left her infertile, at which point she decides she really wanted to become a mother...and then she inexplicably becomes pregnant.]]
* ItIsNotYourTime
** Scully in "One Breath".
** Mulder in "The Blessing Way".
* ItAlwaysRainsAtFunerals: "Beyond the Sea"
* ItMayHelpYouOnYourQuest: Subverted with the spike weapon Mulder's mother directs him to, which he never successfully uses on an alien.
* ItTastesLikeFeet: In "The Unnatural", Mulder bets that the air in his mouth tastes better than Scully's Nonfat Tofutti Rice Dreamsicle.
* IWillPunishYourFriendForYourFailure: At the end of "Drive", AD Kersh threatens Mulder that he will bill Scully for his unauthorised expense.
* TheJerseyDevil: Turns out there isn't one, it was just inspired by a tribe of feral humans and their ancestors living in seclusion.
* JokerJury: In the first part of the series finale, Mulder is captured by U.S. Marines and put before a show tribunal.
* TheKetchupTest
** Used by [[spoiler:Timothy]] in "Three of a Kind".
** Mulder in "Revelations".
* KickTheDog: A literal example in "Fire".
* TheKillerInMe
** Type B in the episode "Chimera". Ellen Adderly was horrified as anybody with the murders of her friend and later her rival in their community. At one point she believed she was about to be attacked by the stringy-haired creature she saw in the mirror. It was found out that she suffers from SplitPersonality and her extreme aggression was how she dealt with her husband's cheating on her.
** The copycat killer in "Grotesque" was a leading investigator in the original case. Did he know he was chasing himself? Possibly, as he specifically requested Mulder who he believed is the only one who could crack the case. However, he seems genuinely appalled and distrustful when Mulder reveals to him that it is him who they are looking for. In addition, he then claims as the original SerialKiller that he was possessed by a demonic force.
* KillSat: Used by the A.I. in "Kill Switch".
* KissMeImVirtual: In "Triangle", Mulder (apparently) travels back in time to 1939, where he swiftly gets entangled in some WorldWarII hijinks involving various individuals who [[ButYouWereThereAndYouAndYou just happen to look identical to important people in his own life]]. Scully's counterpart is a tough-talking undercover OSS agent in a red cocktail dress. Just before he exits the boat, Mulder grabs her for a passionate kiss "[[NowOrNeverKiss in case we never meet again]]." 1939!Scully, of course, responds [[KissKissSlap somewhat differently]].
* LanguageBarrier: Employed from time to time, especially with BlackSpeech languages. When somebody spoke foreign language, the Agents Mulder and Scully were sometimes able to understand as Scully speaks German and is "rusty" in some others, while Mulder claims he had French at high school. The foreign languages were sometimes subtitled for the audience's benefit, but at times viewers were left as clueless as were the characters.
** In "Little Green Men": Mulder travels to Puerto Rico to a carefully watched observatory and he meets there Jorge who is very scared and obviously had a weird encounter. Mulder tries desperately to calm him down and question him, but he only manages to produce some broken basic sentences. Finally, Jorge grabs Mulder’s pen and draws on the wall something that looks like a head of an alien with big eyes.
** "Nisei": Mulder catches and arrests a Japanese spy who is a part of TheConspiracy. It's not clear whether he could speak English, but he was only yelling at Mulder in Japanese. Mulder also doesn't understand his notes which frustrates him.
* LiteralGenie: The female genie in "Je Souhaite".
* LiteralCliffhanger: From "Revelations". An insane businessman grabs a boy and jumps into a paper recycling shredder. When a horrified Scully rushes over, she finds the boy holding onto the railing above the bloody mess.
* LiteralSurveillanceBug: The robo-roaches from "War of the Coprophages". It's implied that rather than spy gadgets, they're actually space probes sent to explore the Earth by a far-off alien civilization.
* {{Lobotomy}}: Gerry Schnauz was a serial lomotomist in "Unruhe". He thought he was helping his victims and that he removed their inner demons. One girl is found dead and one is alive, apathetic and unable to speak.
* LockedRoomMystery
* LosingYourHead: The head after decapitation is still alive in "Leonard Betts".
* MacGyvering: Scully opens a bullet with her bare hands and tries to use the gunpowder to start a fire in "Detour".
* MailerDaemon: The fat-sucking vampire from "2Shy".
* MagiciansAreWizards: Subverted in "The Amazing Maleeni".
* MagicMirror: Several times.
** In "Syzygy", monster-of-the-week teen girls use a mirror to summon up Bloody Mary.
** "Elegy" has a bloody message written on the mirror.
** Every crime scene in "Chimera" involves a broken mirror or some other shiny surface so that the killer could not actually see her true self.
* ManBitesMan
** Mostow bit Agent Nemhauser in "Grotesque".
** If 'vampire bites man' counts, then "Bad Blood", too.
-->'''Skinner:''' The coroner's throat's been bitten.\\
'''Mulder:''' The coroner's dead?\\
'''Skinner:''' No, his throat was ''bitten''. Sort of... gnawed on.
** "Eve" had the EyeScream variety of this trope. Eve 6 bit a guard into his eyeball.
* MaybeMagicMaybeMundane
** The killer in "Grotesque" is eventually revealed to be a profiler who looked too long into the abyss of a particular serial killer and turned into him. Whether this is a psychological effect or transferred demonic possession is left up to the viewer.
** The possibly demonic serial killer and necrophiliac Donnie Pfaster from "Irresistible" and "Orison".
** "Paper Hearts": Did John Lee Roche really kidnap Samantha? Did he have a "psychic nexus" with Mulder as Mulder himself claims? Or did he just extensively research Mulder's background? What about Mulder's dreams?
* MedicalHorror: Happens often enough during the MythArc episodes, but taken about as far as possible (for prime-time TV, at least) in "Sanguinarium," which takes place in a hospital and features death by liposuction, death by plastic surgery and various other horrifying scenes, culminating in a plastic surgeon who has, shall we say, a fool for a patient.
* MetalDetectorCheckpoint: Scully discovers her neck implant this way.
* MindControlConspiracy: In the Lone Gunmen origin story.
* MindScrew: "Milagro"
* MirrorRoutine: "Dreamland"
* TheMirrorShowsYourTrueSelf: "Dreamland" and "Chimera".
* MockingMusic: In "Vienen", Agents Mulder and Doggett are pursued by oil rig crew members who have been infected by the black oil. They are violently banging on the door of the communications room, while Doggett tries to get the radio working. The static changes to The ''Music/RideOfTheValkyries''.
* {{Mockumentary}} / [[FoundFootageFilms Found Footage Episode]]: ''X-Cops'', which is filmed in the style of ''Series/{{Cops}}''.
* MoneyDearBoy: The in-universe reason Jose Chung writes his bestselling novel ''From Outer Space''.
* MotionBlur: "Rush" has a key plot-point where security footage at a high school was found to show a strange blur. Using [[EnhanceButton experimental technology]] to colorize it, the agents reveal the blur is made up of the school colors, suggesting that it comes from the jacket of one of the (superpowered) students.
* MuggingTheMonster: A demon crosses a demonic woman's path in "Terms of Endearment".
* MultiPartEpisode: There are almost as many multi-part episodes of the show as there are stand alone. Most of the mythology episodes ended up being multi-parters though they were rarely named as such.
* {{Mundanger}}: Loads -- mass panic in "War of the Coprophages" (subverted in that there really ''are'' robotic alien cockroaches involved, but they have nothing to do with the deaths in the episode); serial killers in "Grotesque", "Orison" and "Irresistible"; [[TheFamilyThatSlaysTogether one really nasty family]] in "Home"; organized crime in "Hell Money"; a CannibalClan in "Our Town"; an alligator in "Quagmire".
* MurderByCremation: "Hell Money". A gambling ring among Chinese immigrants claims organs as collateral; if you can't pay up (or if you rat), you're disposed of in a crematorium. Alive.
* MurderByMistake: [[spoiler:Melissa Scully is shot instead of her sister]] in "The Blessing Way".
* MurderSuicide: In "Demons", Mulder's weapon has been used in a crime and he doesn't remember what happened. He's arrested, but it's revealed that the couple's death was a murder-suicide, and Mulder's released.
* MysteryCult: The Kindred, the Church of the Red Museum, and the Temple of the Seven Stars.
[[/folder]]

[[folder:N-T]]
* NeurodiversityIsSupernatural
** In the episode "Fallen Angel", it's implied that aliens are responsible for Max's epilepsy.
** In "E.B.E.", Mulder suggests that Gulf War syndrome is the result of alien encounters.
** A notable episode featured an adult with Pervasive Developmental Disorder (also referred to in the episode by its old name, "Atypical Autism"); he was portrayed quite realistically despite his connection to the paranormal.
* NewYearsResolution: Scully has a good one in "How the Ghosts Stole Christmas" - apparently it's not to follow Mulder on all his crazy off-side projects.
* NoCelebritiesWereHarmed: In "F.P.S." the pair meet a parody of then-gaming celebrity Dennis "Thresh" Fong.
* NoOSHACompliance: In "Beyond the Sea", the climactic chase scene takes place in an abandoned brewery that is falling apart. The villain steps through a wooden plank bridge and falls several floors to his death.
* NotListeningToMeAreYou: At least twice:
** "Home": Scully to Mulder who is a bit spaced out and playing with a baseball.
-->'''Scully''': Meanwhile, I've quit the FBI and become a spokesperson for the Ab-roller.
** "all things": Mulder to Scully who is preoccupied with her salad.
--> '''Mulder''': And I'm not wearing any pants right now.
* NotSoStoic: Scully gets several of these moments -- the best example is probably "Irresistible," where she finally realizes Mulder won't think any less of her for seeing her break down after a traumatic experience.
* NotTheNessie: "Quagmire" has Mulder and Scully investigating reports of a lake monster. In one scene the owner of the local tourist trap is shown faking some monster footprints, whereupon he gets eaten by the real monster, a large alligator. However, the audience can see there really is a giant serpent in the lake.
* NothingIsScarier: The EldritchAbomination from ''X-Cops''.
* NubileSavage: "The Jersey Devil". Her legs were rather smooth for someone living in the woods of Jersey.
* NuclearNasty: Flukeman from "The Host" is a monster created by radiation.
* ObliviousToLove: The sixth season episode "The Rain King" revolves around this trope. {{Adorkable}} weatherman Holman Hardt has had a crush on [[spoiler:Sheila]] since his high school days, and the [[spoiler:the odd weather]] is the unconscious result of his unspoken affection for her. Sheila also has a thing for Mulder which is unnoticed by the latter, at least until she plants him with a kiss.
* ObfuscatingDisability: [[spoiler:"The Amazing Maleeni"]]
* OceanicAirlines: "Synchrony": Agents Mulder and Scully search the hotel room of the mysterious old guy who seems to have come [[TimeTravel from the future]]. Scully finds a note pad in his room. There are the words "Pan Oceanic flight #1701" written on it.
* OldFlameFizzle: Scully and Daniel Waterston in "all things," though it wasn't mutual. He remained very much in love with her through the end of the episode, while she realized that over a decade had passed since she was a medical student seduced by her (very married) professor, and that she likes her life and who she is now. This realization also led to the start of [[spoiler: Mulder and Scully's romantic/sexual relationship.]]
* OlderThanTheyLook:
** Eugene Victor Tooms from "Squeeze" and "Tooms" was a genetic mutant and SerialKiller who needed [[PickyPeopleEater human livers]] to hibernate. He looked to be in his late twenties in 1993, but his first murder had occurred in 1903.
** CannibalClan in "Our Town" preserved their youthful look thanks to their [[IAmAHumanitarian special diet]].
** Alfred Fellig from "Tithonus" was a photgrapher who gained immortality by tricking Death.
* OminousVisualGlitch:
** In "Wetwired", distortions of the picture implied that a person is under influence of subliminal transmission that triggered the person's worst fears and compelled them to kill.
** In "Demons", Mulder underwent an extreme psycho-treatment to induce his memories of Samantha's abduction. His "memories" (probably hallucinations) were showed in freaky colours with distorted people, and the picture is intentionally grainy.
** "Kill Switch": Mulder is trapped in a virtual reality simulator. When he realizes that it's not real, the reality from his perspective starts to short out. He sees the glitches and fake Scully dissolves into an image of animated person.
* TheOner: "Triangle" has several, as an homage to ''Theatre/{{Rope}}''.
* OriginsEpisode: "Musings of a Cigarette Man" for C.G.B. Spender, "Unusual Suspects" for the Lone Gunmen.
* OutOfCharacterMoment: Played in-universe; the phenomenon in "Syzygy" causes not only Mulder and Scully to act in ways they normally wouldn't, but also apparently the entire town it's focused around; the normally calm and rational high school principal turns into a ranting fundamentalist nutcase, for example.
* PapaWolf: [[spoiler:Howard Graves]] in "Shadows". Do ''not'' mess with his secretary/surrogate daughter [[spoiler:even ''after'' he's dead]].
* PedestrianCrushesCar: "Salvage" starts out with a car being almost cleaved in half after running into someone.
* ThePeepingTom: "Red Museum" features a man who secretly records everyone living in his building from inside their bathrooms.
* PercussiveTherapy:
** Mulder gets very frustrated in "Bad Blood" and he gives full vent to his anger in kicking the hell out of a trash can violently. (He killed a teen by jamming a wooden stake in his chest and the FBI is being sued for $446 million dollars. Anyway, Mulder had been drugged.)
** In a less humorous example, in "Sein Und Zeit" Mulder reacts by attacking his desk when Scully tells him that [[spoiler:his mother committed suicide]].
** In "Anasazi", Mulder thinks he received a fake tape with "gibberish" instead of top secret government files. He hits a pencil holder and smashes it against the wall. But the files are actually encrypted. Poor Mulder has been drugged, so he ends up punching Assistant Director Skinner a moment later.
** "Wetwired": Mulder is on his way to identify a body [[spoiler:which might be Scully]]. The messenger of his jerk of an informant follows him and insists that he keeps investigating the case, yet still gives him only super vague leads. Utterly frustrated, Mulder kicks the door of the Plain-clothed Man's car.
* PinocchioSyndrome: [[spoiler: "The Unnatural" has an alien who became a man thanks to his love of baseball.]]
* PhlebotinumDuJour: A couple of times.
** MagicalParticleAccelerator: That's how the MonsterOfTheWeek got his killing shadow in "Soft Light".
** {{Nanomachines}}: The cause of Skinner's poisoning in "S.R. 819".
* PhoneCallFromTheDead: In a Myth Arc episode, Scully gets a phone call from her dead sister. This ends up leading her to a girl who is her biological daughter, created using the ovum extracted from her body.
* PresentPeeking: In "Christmas Carol", teenage Melissa and Dana go to the tree to peek at their presents. Mrs. Scully comes to them as well, and they open their presents with golden crosses together.
* PrisonerExchange: Mulder performs such a trade in "End Game" between Scully and [[spoiler:an alien clone he believes is his sister Samantha]].
* PsychicAssistedSuicide: The method of murder in "Pusher", powered by a CompellingVoice.
* PunishmentBox: "Trevor" opens with a prisoner being punished by being locked in a small shed... right before a tornado hits.
* PyroManiac: The British arsonist in "Fire".
* RaceAgainstTheClock: Several times.
** "Beyond the Sea": The investigating team has 5 days to find two kidnapped and tortured teenagers.
** In "731", Mulder doesn't have much time to separate a boxcar with an alien-human hybrid and a time bomb from the rest of the train. He also needs to find out the code to open the sealed door.
** In "S.R. 819", Mulder and Scully have one day to find out who poisoned Skinner and they need to find a cure as well.
* RashomonStyle: PlayedForLaughs in some humorous episodes, most notably "Jose Chung's ''From Outer Space''" and "Bad Blood".
* RealityWritingBook: In "Milagro", a writer moves in to Scully's apartment building and starts affecting her life with his writing.
* {{Reincarnation}}
** In "The Field Where I Died", Mulder comes to believe that he was married to a female member of a cult in a past life, and under hypnosis claims to remember not only her but Scully, Samantha and Cancer Man as reincarnated friends and enemies respectively.
** In "Born Again", a cop was reincarnated to a [[CreepyChild little girl]]. When she was eight, the revenge on the cop's murderers was on.
** The character who swore revenge came back [[spoiler:as a fly]] in "The List".
** In "Hellbound", the reincarnation of a man [[FlayedAlive skinned alive]] in the 1860s comes back as a police officer in each of his reincarnations to avenge his own death and make sure the crimes are never solved, as his never was.
* ReminiscingAboutYourVictims: A villain of the week attempts to convince Mulder that he killed Mulder's sister by doing this. Mulder eventually call bullshit on him.
* RevengeByProxy: "The Walk", "Theef" and "Redrum".
* ARiddleWrappedInAMysteryInsideAnEnigma: The episode "Patient X" contains a variant on the trope phrasing. Agent Mulder, who has grown skeptical of the existence of extraterrestrials but instead believes the alien conspiracy to be a lie concocted by the military to hide ''a different'' and all the more sinister scheme, describes his belief in "a conspiracy wrapped in a plot inside a government agenda."
* RoomFullOfCrazy
** The ConspiracyTheorist who believes in aliens and who wants to be abducted in "Jose Chung's ''From Outer Space''" has a corner in his room which is a nice foil to Mulder's office. He even has a similar poster but the message reads "I believe".
** In "Grotesque", Mulder sinks deep into ugliness and madness of the case. At one point, the walls of his apartment are completely covered with gargoyle sketches. Mostow's studio also counts.
* RoomFullOfZombies: In "Millennium", there's a basement full of zombies.
* RubeGoldbergHatesYourGuts: "The Goldberg Variations" involved a person who manipulated other people's luck, resulting in rather bizarre ends for them.
* RussianRoulette: The climax of "Pusher".
* SawStarWarsTwentySevenTimes:
** Mulder reveals in the episode "Hollywood A.D." that he's seen ''Film/Plan9FromOuterSpace'' forty-two times. He claims that the sheer badness of the film numbs his brain, allowing him to make intuitive leaps and solve problems that have him stumped.
--> '''Scully:''' You've seen this movie ''42 times?''\\
'''Mulder:''' Yes.\\
'''Scully:''' Doesn't that make you sad? It makes ''me'' sad.
** In an earlier episode, the agents ran across a woman who was convinced she'd been impregnated by Luke Skywalker. This becomes even more hilarious when it is revealed she's seen ''Franchise/StarWars'' 368 times, and was hoping to break 400 by Memorial Day.
* ScreamingBirth: [[spoiler:Scully]] at the end of season 8.
* SeeTheInvisible: Tapping yellow powder in "Je Souhaite".
* SerialKiller: Several times. Most of them are really horrifying.
* SeriesFauxnale: Season 7's "Requiem" was designed to be the series finale. Mulder and Scully return to the site of their first case together, pretty much every major character gets an appearance, and the episode ends in true X-Files fashion in which [[spoiler: Mulder is abducted and Scully finds out she's pregnant without conclusion or explanation for either.]] A lot of fans treat it this way, since many regard season's 8 and 9 as subpar to the rest of the series.
* SetRightWhatOnceWentWrong: A variation in the episode [[SdrawkcabName "Redrum"]]. Prosecutor Martin Wells wakes up in prison with no idea why he is there and is shot dead by his [[spoiler: father-in-law]] at the beginning of the episode. As the week progresses, he realizes he is being sent through the week backwards, but does not know why until he meets with [[spoiler: his wife's killer. He is able to save his wife, but he [[BittersweetEnding goes to prison at the end of the episode]] for evidence suppression, a punishment he feels he deserves.]]
* ShirtlessScene
** Mulder was shirtless fairly often.
** Shirtless Skinner appeared in "Tunguska".
* SingleIssuePsychology: In "Fire" Mulder is revealed to have pyrophobia, which goes back to a single traumatic event in his childhood. He faces his fear in that episode and it never comes up again.
* SheIsNotMyGirlfriend
** Mulder and Scully both have to clarify this to [[EveryoneCanSeeIt others]] on several occasions, sometimes more than once to the same person.
-->'''Mulder:''' I do not ''gaze'' at Agent Scully.
** Scully also says this of Mulder in the second movie, except with "husband" instead of "boyfriend" [[spoiler: -- because he ''is'' her boyfriend at that point]].
* TheShowGoesHollywood: "Hollywood A.D."
* ShrunkenHead: The episode "Our Town" the semi-{{Mundanger}}ous Perp of the Week has some shrunken heads he ''claims'' are fake, non-human souvenier trinkets from his travels as a young man. But then it turns out that he and his [[CannibalClan small town/family]] are OlderThanTheyLook, keeping themselves young through [[ImAHumanitarian ritual cannibalism]] which he had learned from HollywoodNatives during those same travels.
* SiliconBasedLife: "Firewalker"
* SinisterMinister: Common in the religiously-themed episodes.
* SomeoneToRememberHimBy: [[spoiler:Scully finds out she's pregnant immediately after Mulder is PutOnABus.]]
* SomethingCompletelyDifferent
* SomethingElseAlsoRises: In "Dreamland II" [[TheMenInBlack Morris Fletcher]] [[BodySnatcher as]] [[FreakyFridayFlip Mulder]] tries to seduce Scully. He holds a bottle of champagne in his lap which pops open and overflows.
* SpontaneousHumanCombustion: Suggested as an explanation for mysterious deaths in "Fire", "Soft Light", and "Trevor". [[spoiler:It always turns out to be something else.]]
* StagedShooting: "Amazing Maleeni" and "Three of a Kind".
* StalkerWithACrush: Padgett in "Milagro", who's in love with Scully.
* StaringKid: Used in the episode "Fearful Symmetry".
* StepfordSuburbia: A community hides some terrible secret which is covered up with a sweet veneer. Explored in "Arcadia" and "Chimera".
* StockEpisodeTitles: Several examples especially but not exclusively from the early seasons. Examples include "Shadows", "Ghost in the Machine", "Ice", "Fire", "Fallen Angel", "Blood" or "Drive".
* SuperCellReception: At the end of "Anasazi", Mulder makes a cell phone call, while stranded in the middle of a desert inside a boxcar buried underground.
* SuperWindowJump: One of the clone doctors escapes from the alien bounty hunter by jumping out the window from about four stories up in "Colony".
* SurpassedTheTeacher: "Grotesque" implies that Mulder surpassed Bill Patterson in profiling skills. They had a complicated teacher/student relationship for many reasons.
* SympatheticPOV
** "Hungry" gives this to the MonsterOfTheWeek, who is just trying to get by and live with the trouble his power/affliction causes. Mulder and Scully don't appear until the end [[spoiler:and then they shoot him.]]
** "Musings of a Cigarette-Smoking Man" gives one to CSM.
* SympathyForTheDevil: The episode "Musings of a Cigarette-Smoking Man".
* TableSpace: "Fallen Angel" features Scully and then Mulder sitting at a super long table when they have a responsibility hearing.
* TagAlongActor: The episode "Hollywood A.D." does this with a movie director instead of actors following Mulder and Scully on an investigation.
* TaintedVeins: Skinner in "S.R. 819".
* TearYourFaceOff: One MonsterOfTheWeek conducts a ritual that will allow him to change his face by [[HumanSacrifice killing hospital patients as sacrifice]]. In the end, he cuts his face with a scalpel and rips it off, revealing the new one underneath it. Mulder later finds the old one lying on the floor.
* ThereIsOnlyOneBed
** Subverted in "Rain King". Mulder and Scully have to share a hotel room with just one bed. They're kind of annoyed over the hotel assuming they wouldn't mind sharing a room, but no real tension or embarrassment between them comes of it.
** Played just a little straighter in "Arcadia", where they're [[UndercoverAsLovers undercover as a married couple]]. Mulder has some fun teasing Scully by suggesting that she get in bed with him, but it's still not treated like a big deal.
* ThereIsNoRuleSix: A variation from episode "Bad Blood":
-->'''Scully:''' First of all, Mulder, if the family of Ronnie Strickland does sue the FBI for, I believe the figure is 446 million dollars, you and I will almost certainly be named co-defendants. And second of all... I don't even have a second of all, Mulder. 446 million dollars.
* ThirdPersonPerson: Duane Barry's not crazy!
* TimeyWimeyBall: Apparently, a rip in space-time can cause you to [[FreakyFriday switch bodies]] with someone near you...[[FridgeLogic Huh?]]
* TitleDrop: In the episode "Travelers", it's explained unsolved cases were filed under "U", until space in the filing cabinets ran out, so they were then put under "X" which had e[[IncrediblyLamePun x]]tra room. Thus, the unsolved cases are [[ExactlyWhatItSaysOnTheTin "X" files]].
* ToadLicking: The episode "Quagmire" had a bunch of slackers licking toads to get high.
-->'''Snorkel Guy:''' Dude, what is wrong with you? You made me drop my toad!
* TooDumbToLive: The Stokes brothers in "Je Souhaite". And '''how!'''
* TheTopicOfCancer:
** Scully almost died of alien-induced cancer. Other abductees were not as lucky.
** In "Leonard Betts", the Monster of the Week was a man made entirely of cancerous tissue. He could regenerate the ''[[GoodThingYouCanHeal loss of his head]]'' and had to eat cancerous tissue removed from surgery patients (he worked in a hospital). Mulder and Scully {{squick}}ed in-universe when they found out.
* TotallyRadical: In "First-Person Shooter" and "Kill Switch". Doubly unforgivable as both episodes were written by cyberpunk authors Creator/WilliamGibson and Tom Maddox, who should know better. However, both Gibson and Maddox place blame on Chris Carter for this, him having made revisions to both scripts before filming.
* TownWithADarkSecret: Lots of them. Played for humor in "Arcadia".
* TragicVillain: Rob Roberts in "Hungry".
* TrappedInASinkingCar: In episode "Nothing Important Happened Today", a female Super Soldier lures a man into taking her home and forces his car over the edge of a bridge and into the water. She then uses her immunity to death to hold him underwater until he drowns.
* {{Tulpa}}: A MonsterOfTheWeek, when the president of a homeowners' association created one to enforce the neighborhood rules.
[[/folder]]

[[folder:U-Z]]
* UhOhEyes: The monsters' eyes sometimes indicated the level of their evil.
** BlackEyesOfEvil: The brain-eating struggling monster in "Hunger".
** CreepyBlueEyes: John Barnett's blue eyes were glassy and glazed over, and they appeared dead. Even the pupils were blueish.
** HellishPupils: Animal-like pupils were used for a satanic demon in "Die Hand die Verletzt", then for a South American Indian shaman in "Teso dos Bichos" and for a demonic woman in "Terms of Endearment".
** RedEyesTakeWarning: Tree-like-looking primitive men with red piercing eyes appeared in "Detour".
** SupernaturalGoldEyes: Eugene Victor Tooms in "Squeeze" and "Tooms" had yellowish eyes, the colour of bile.
* UncannyVillage: "Arcadia" features a seemingly peaceful American-dream community controlled by Home Owner Association, represented mainly by President Gene Gogolak. They have strict rules and regulations about everything and observing them is enforced by death threat.
* UndercoverAsLovers: "Arcadia"
* UnfamiliarCeiling: Mulder doesn't recollect why he's not at his own place in "Anasazi" twice. He's confused when wakes up at Scully's and then the same repeats at Albert Hosteen's in New Mexico.
* UnreliableNarrator: "Jose Chung's ''From Outer Space''", "Musings of a Cigarette-Smoking Man", "Gethsemane", "Bad Blood". There's probably more examples. They really like this one.
* TheUnreveal: The source of the teens' super-speed in "Rush" is never explained. All that is known is they go into a cave, interact with a strange metal, and emerge with superpowers.
* UnusualEuphemism: "Jose Chung's ''From Outer Space''" and Detective Manners, who raises the word "bleep" to an art form.
* VampiresAreSexGods: Even Agent Scully admits that vampires are supposed to be extremely charming and seductive.
* TheVietnamWar
** The villains from the episodes "Sleepless" and "Unrequited".
** Skinner is also a Vietnam vet, and his experiences feature in episodes like "One Breath" and "Avatar".
* VisibleInvisibility: "Fallen Angel" featured invisible aliens that were shown to the audience through movements of a rushing camera or distortion of the background.
* VoluntaryShapeshifting: Eddie Van Blundt from "Small Potatoes".
* VomitDiscretionShot: "Clyde Bruckman's Final Repose", "Jose Chung's ''From Outer Space''" and "Three of a Kind".
* WakingUpAtTheMorgue: In "Leonard Betts" after decapitation, no less.
* WastefulWishing: Anson Stokes' first wish in "Je Souhaite" was that his boss would shut the hell up. He did.
* WaterSourceTampering: In "Anasazi", TheSyndicate puts LSD into Mulder's water supply, causing erratic behavior that discredits both him and the case he is currently working on.
* WhamEpisode: The show was quite fond of these.
* WhamLine:
** In "Clyde Bruckman's Final Repose" -- "How do I die?" -- "You don't." First hint that Scully is immortal.
** In "Leonard Betts" -- "I'm sorry... but you've got something I need." It means that Scully got cancer.
* WhatHappenedToTheMouse: Mulder wears a wedding ring in "Travelers", which is set just a year before the start of the main plot. Of course no reference to him ever being married occurs anywhere else. And when there is his profile on screen, his marital status reads "single" or "unmarried".
* WhatKindOfLamePowerIsHeartAnyway: Jerry Schnauz in ''Unruhe'' has the most useless psychic superpower ever: unconsciously imprinting his schizophrenic delusions onto undeveloped film.
* WholePlotReference: "Ice" is one for ''Film/TheThing1982''. "Humbug" is one for Tom Reamy's 1977 short story "The Detweiler Boy".
* WhoWantsToLiveForever: "Tithonus"
* WhyDidItHaveToBeSnakes
** Mulder suffers from pyrophobia, and guess what? He has to face it in "Fire". It's fair to note that it was not accidental as Phoebe Green requested his help on the case and she knew about his fear.
** Subverted with Agent Scully. In "One Breath", her mother tells a story how she felt guilty for shooting a snake with her new BB gun. Although deathly afraid of snakes, she held the snake and it died in her hands. When Mulder and Scully investigate cases involving snakes, she isn't exactly on edge ("Die Hand die Verletzt") and she even gets a tattoo of a snake eating its own tail in "Never Again". On the other hand, there are lots of snakes in "Signs and Wonders", but even Mulder who doesn't suffer from this phobia is very nervous around them.
** All the perpetrators in "Blood" were phobic and the exposure to insecticide heightened their already existing phobia to an unbearable level. One killer was claustrophobic (Why did it have to be a crowded elevator?), another one had a paranoia about rape (Why did it have to be a mechanic in a garage at night?) and the last one was AfraidOfBlood (Why did it have to be blood?).
* WrittenInAbsence
** Scully's [[AlienAbduction abduction]] -- an event that would go on to shape the entire MythArc, as well as Mulder and Scully's relationship and CharacterDevelopment throughout the rest of the show -- was written in simply to get Gillian Anderson out of the way while she was heavily pregnant in RealLife.
** There are also several more episodes where either Mulder or Scully are mostly absent while their actors were off doing other things -- especially in season five, while they were filming the first movie.
** In "Fearful Symmetry", the Lone Gunmen appeared, but Langley was absent. The real-life reason? Dean Haglund was booked to appear on a ''Series/{{Sliders}}'' episode ("Fever"), which was filming at the same time.
* YouHaveToBelieveMe: Mulder to Scully in "Folie à Deux", leading to this:
-->'''Mulder:''' Scully, you ''have'' to believe me. No-one on this whole damn planet does or ever will. You're my one in five billion.
* YouLookFamiliar
** Larry Musser appeared on the show four times. He was Sheriff John Oakes in "Die Hand die verletzt, Detective '''bleeping''' Manners in "Jose Chung's ''From Outer Space''", ex-marine in Denny Markham in "Unrequited" and PD Captain Jack Bonsaint in "Chinga".
** Terry O'Quinn as a three-peat. First he played Lt. Tillman in "Aubrey", then bomb expert Darius Michaud in ''[[Film/TheXFilesFightTheFuture Fight the Future]]'', and finally one of the Consortium in "Trust No 1".
** Chris Owens also appeared several times as a young Smoking Man before being cast as Agent Spender. [[spoiler:Considering the two characters' relation as father and son, this was likely intentional.]]
** The trio of stoners in "War of the Coprophages" turn up again in "Quagmire".
** Nicholas Lea, as mentioned above, had a guest spot in "Genderbender" before being cast as Krycek.
** William B. Davis is credited as "CIA Agent" in the episode Young at Heart. It's unclear whether the character is meant to be the Smoking Man, since up to then Davis had only appeared in the Pilot.
* YourHeadASplode: "Drive" features a disease that made an ear explode.
* YourMom: In "Clyde Brucman's Final Repose", The Stupendous Yappi insults Mulder back with the father variant of the joke:
-->'''Mulder:''' Mister Yappi, read this thought. ''(Yappi stares at him, then suddenly lunges back and raises his eyebrow)''\\
'''Yappi:''' So's your old man!
* YourVampiresSuck: "Bad Blood"
* YouthIsWastedOnTheDumb: "Rush"
[[/folder]]

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