Formerly a renowned profiler, he became something of a joke at the Bureau when he started to pursue an obscure side project known only as the "X Files", but he soon drew attention from more sinister quarters...
Always Save the Girl: 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.)
Ambiguously Jewish: On more than one occasion, anti-Semitics accuse him of looking Jewish; Mulder always refuses to answer. What we know about his family background makes it somewhat unlikely that he actually is.
Anyone Can Die: For, like, two episodes in season 8. Oh, and at the end of season 2. There's probably one or two more examples over the show's run. Mulder dies kind of a lot, actually. Never Killed Off for Real, however.
Badass Bookworm: For some values of "badass," at least, although he does in fact get beat up quite a lot.
Bunny-Ears Lawyer: The FBI tolerates his obsession with the paranormal because he's a very, very, very good forensic psychologist. Mulder was a very strongly right-brained intuitive, who also engaged in free association thinking, and was able to detach his mind from conventional preconceptions. He was so good, in fact, that he'd earned the moniker 'Spooky' before even opening the X-Files: his partner at the time thought his ability to profile and understand people was downright uncanny.
This Loser Is You: Fox (the network, that is) liked this trope a lot during The Nineties. Mulder is rarely listened to, is generally mocked by friends and coworkers alike for his conspiracy theories and his passionate, often blind belief in the supernatural, uses phone sex lines, has a huge Porn Stash, and is honestly kind of a belligerent dick throughout most of the first season.
What the Hell, Hero?: He got this several times in the first four seasons ("Paper Hearts" is perhaps the best example), mostly from Scully and sometimes Skinner. After that he managed to get a better grip on his issues.
A forensic pathologist with a background in physics, she was assigned to work with Mulder ostensibly in order to use her scientific knowledge debunk his work; however, she was less predictable than the conspiracy had hoped.
Agent Mulder: Later in the series, she was accepting the paranormal explanations. Agent Doggett tried to scully her.
All Girls Want Bad Boys: Has an amazing talent for picking guys who turn out to be messed up in the head and often outright psycho. Mulder is probably the most stable person she's ever been with, and that's saying a lot.
Arbitrary Skepticism: Scully remains a hardcore skeptic long after she's seen shape-shifting aliens, watched Mulder be mind-controlled into things he'd never do on his own, etc. It's somewhat justified, 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.
Badass Bookworm: A fully qualified medical doctor and pathologist and forensic examiner. What's fine is that Mulder and Scully are sometimes actually shown doing research and reading.
The Chosen One: It's implied in many of the religiously-themed episodes that God has some sort of special task in mind for her, although exactly what she's called to do is never made clear. Unfortunately, this arc comes to a somewhat unsatisfactory end when she gives in to her anger and kills Donnie Pfaster, whom God had put in front of her as a test in "Orison".
Cloudcuckoolander's Minder: Mulder isn't quite a Cloudcuckoolander in the usual sense (though he comes across that way to lots of people in-universe), but Scully has the traditional role of stopping him from doing stupid reckless things, putting together the actual evidence to support his weird leaps of intuition, explaining and defending his crazy ideas to other people, etc.
Combat Stilettos: She wears heels nearly all the time, no matter how much running and shooting she expects to need to do. Of course, when you're a five foot two FBI agent every inch probably helps.
Crisis of Faith: Scully started the show as a non-practising Catholic. Part of her Character Arc 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 The Church said.
Deadly Bath: 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").
Medical Rape and Impregnate: It's eventually implied that something along these lines (but involving alien tech and probably extraterrestrial DNA) happened to Scully during her abduction early in season 2.
Military Brat: Her father was in the Navy, as is her elder brother.
Ms. Fanservice: Downplayed. FOX was reluctant to cast Gillian Anderson as a lead, saying they wanted someone who'd look better in a swimsuit. Chris Carter informed them that Scully would not be wearing any swimsuits. However, Agent Scully was the only prominent female on the show and looked cute enough. Later as the series progressed, she had her fair share of more typically fanservicey moments.
My Biological Clock Is Ticking: 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.
Hazy Feel Turn: It's always pretty clear that he's not a good guy, but he constantly switches between different bad guy factions, and his interests occasionally even coincide with those of Mulder and Scully, resulting in brief Enemy Mine situations.
Hellbent For Leather: Usually wears a leather jacket, though thanks to the beatings he often takes, it's rarely the same one from episode to episode.
The Mole: When he's introduced, although it doesn't last long before his cover's blown.
Obfuscating Incompetence: Pay close attention to his episodes and you'll realize he actually gets away with a lot more than he appears to. A perfect example would be "Tunguska", where he was the one who hired the Russian assassin who (temporarily) royally screwed up the Syndicate's plans.
Russian Guy Suffers Most: His parents were Cold War immigrants. (If he was being honest for once when he said that. He is fluent in Russian, though.)
Psycho Ex-Girlfriend: The psycho part is not obvious until "The Sixth Extinction", where she visits Mulder, who's confined in a psychiatric hospital and being Mind Raped by psychic influence from an alien artifact, and makes a speech that can be summed up as "I've always loved you, Fox, and now that you're in five-point restraints we can finally be together."
Romantic False Lead: Seemed to exist mainly for the purpose of teasing the fans and making Scully jealous. (Mulder gave little sign of still having anything but platonic feelings toward her, however, although she was clearly carrying a torch for him.)
Agent Jeffrey Spender (Chris Owens)
Assigned to the X-Files as Agent Fowley's partner when they replace Mulder and Scully on the X-Files at the beginning of season 6. Mulder's half-brother, fathered by the Cigarette Smoking Man.
Jerkass: He's put in charge of X-Files department, a department that Mulder rescued and gave his soul into the work. Spender just sits in his office and keeps destroying documents about prospective cases.
Ooh, Me Accent's Slipping: His thick Brooklyn accent comes and goes, though considering that the character is supposed to be from Georgia by way of Brooklyn, an inconsistent accent would be in-character.
No First Name Given: Only his surname is known. Scully realizes she didn't know his first name after he died, although it was weird for her not to remember it as they were on friendly terms and he helped her and Mulder many times.
Agent Leyla Harrison (Jolie Jenkins)
Leyla Harrison worked in the FBI's accounting office, where she processed Mulder's and Scully's expense reports and thereby knew more about their activities than almost anyone. She briefly landed her dream assignment of actually working on the X-Files.The character was created as an homage to and named after a prominent Internet fan and Fan Fiction writer who passed away from cancer.
New Meat: She's been at the FBI for some time, but it's her first field work. She gets on Doggett's nerve quite a bit.
Tuckerization: She was named after a real person, in this case a devoted fan fic writer
The Lone Gunmen
An unlikely trio of conspiracy theorists who publish an underground newsletter called The Magic Bullet. Old friends of Mulder's, they occasionally show up to help out Mulder and Scully, usually by doing research (as well as providing comic relief).Late in the show's run, the Gunmen received their own short-lived spinoff series.
What Happened to the Mouse?: Charlie is seen only in season 1 at Captain Scully's funeral and as a boy in flashbacks. He is only mentioned, giving his love, sending presents or promising to call, but he never appeared personally for holidays or for family crises, e.g. when his sisters were dying.
Opening a Can of Clones: By the time the Truth about Samantha is finally revealed, so many fake Samanthas had appeared that both Mulder and the audience had nearly given up on ever figuring the whole thing out.
Token Good Teammate: Mulder's dad was a member of the Syndicate, but while he was far from a saint, he was pretty much the only member who voiced any objections to the really, really evil stuff the group was doing right from the start.
A mysterious and sinister group who essentially rule the world from behind the scenes. They're determined to conceal the existence of extraterrestrial life from humanity by any means necessary, but their motivation and ultimate goals remain unclear for much of the series.Despite the name, not actually an example of The Syndicate. The term is actually rarely used on the show, so you'll often see fans referring to them as "the Consortium" or just "the Conspiracy."
The Adjectival Man: Members are listed in the show's credits as "Black-Haired Man", "Crew Cut Man", and the like.
The closest thing the show has to a main villain, a constantly chain-smoking older man who likes to skulk around being ominous. He's clearly associated with the grand government conspiracy Mulder and Scully are trying to uncover, but little is known about what he's really up to for quite a while.
The Atoner: He claims to be one in "En Ami." Ultimately it's implied that while he might have some desire for redemption, it's only in the self-indulgent way where he doesn't want it enough to actually change.
Arson, Murder, and Jaywalking: He's responsible for the assassination of at least one democratically elected world leader, the abduction, medical rape and torture of hundreds or thousands of individuals, and making sure the Buffalo Bills never win a Superbowl. Supposedly.
Ascended Extra: Was originally intended to be just a mysterious figure holding a cigarette. Fortunately the actor was able to rise to the occasion when his role expanded. An interesting example, as Davis originally read for the larger (within the Pilot) role of an FBI bigwig (played by Ken Camroux), and received his throwaway role as consolation. One character became one of the show's main villains; the other appeared only in a handful of episodes.
Calling Card: A still-burning Morley cigarette on the ground or in an office ashtray will indicate he's been there very recently—these seem to be left intentionally by him to toy with or intimidate his opponents or send a message. In the episode "The End", the imprisoned failed assassin hired by the Syndicate receives a threatening message on a cut-out side of a Morley carton. Right before he gets shot by the guard, he receives another Morley carton side with no message on it. It is not certain that the prisoner recognized the calling card, but the viewer does.
The Dragon: His exact role in the Syndicate isn't clear, but it's implied he's outranked by Strughold, the Well-Manicured Man and the other elders. In this context, CSM's most frequently seen being chewed out for a security breach or botched cover-up operation.
Fan Nickname: Cancer Man. (Mulder and Scully each called him that exactly once, but the fans picked it up and ran with it.)
Faux Affably Evil: He tries to pass himself off as Affably Evil, telling both Mulder and Scully that he likes them on more than one occasion. They never buy it.
Not So Different: His private life turned out to be not dissimilar from Mulder's. Sure, he's got unlimited reach (Screw you, Bills!), but he can't use it to live openly or extravagantly, so he goes home to his cruddy apartment (with no wife or kids to greet him) and watches b-movies.
One Last Smoke: In the final episode, he takes one last drag, flicks away the butt, then calmly waits until he gets incinerated an airstrike.
A British gentleman who's one of the less overtly malevolent members of the conspiracy. His Code Name is never actually used in the show, but appears in the end credits (as with several other Syndicate members).
Alien Blood: The Black Oil, which is actually their life blood, and at least once suggested to be the real Big Bad controlling the aliens.
Face Full of Alien Wing-Wong: They reproduce through the Black Oil. After it invades a human body, it will produce an alien inside the person's body, which will eventually be ripped open when the alien wants out.
Paranoia Fuel: It hides in petroleum deposits. Which means, it can be transported and infiltrate EVERYWHERE. Not to mention it can simply emerge from the ground, right under your feet, and crawl up through your skin inside you.
A humanoid mutant with characteristics of invertebrate flatworm physiology. Created by radioactive waste, he/she/it (despite its name, it's actually a hermaphrodite) lurks within the waters of New Jersey's sewer systems. Known to bite humans with its scolex-like mouth and inject them with its own parasitic larval offspring. It's implied he can also reproduce asexually, as when a real flatworm is cut in half and develops into two separate organisms. Though it's possible that only one half of him survived getting chopped, and was able to regenerate itself.Flukeman only appeared in one episode, but became very famous with the fans and even causal viewers, and has been immortalized in the form of figurines, models, Pez dispensers, action figures, etc. Also was referenced several times in future episodes as a Running Gag.
Ambiguously Human: They never really explain whether he was a man who got turned into a flukeworm or a flukeworm who got turned into a man.
Which is a bit of a goof, since 1) it's based on a tapeworm scolex, and 2) scolexes aren't mouthparts, they go on the opposite end so the tapeworm can anchor itself to the intestinal wall and eat with the other end.
What Measure Is a Non-Human?: At one point in the episode, the authorities want to try it as a suspect, and it's mentioned that there are plans to have it psychologically evaluated. Mulder reacts by insisting that it's not a human, but an instinctively vicious monster.
Duane Barry (Steve Railsback)
A former FBI agent who escapes from an insane asylum after claiming he was abducted by aliens. Appeared in "Duane Barry" and "Ascension".
Maybe Magic, Maybe Mundane: He changes his appearance several times, including into a demonic form. In Irresistible it appears his transformations are Scully's panicked delusions, but in Orison they appear real.