The X-Files is known for its sci-fi storylines but every so often it reaches out a toe and dips it squarely into the horror genre. The more horror-focused episodes tend to be the self-contained monster-of-the-week outings, largely separate from the series’ overarching alien mythology story arc. This makes them perfect to view as standalone stories—and also perfect to watch on a crisp October night in the lead-up to Halloween.
There’s an X-Files episode for every mood, so some of the episodes on this list are truly scary—the show’s writers knew exactly how to get in your head and fuel some memorable nightmares—while others have creepy elements that are lightened by comedy. So come join Fox Mulder (David Duchovny) and Dana Scully (Gillian Anderson) for some classic spooks and scares—but be warned, there are spoilers ahead!
“Squeeze” (Season 1, Episode 3)

“Squeeze” is the very first monster-of-the-week episode of The X-Files and also the first episode I ever saw. It doesn’t have much to do with Mulder’s alien obsession but I stand by it being a brilliant introduction to the series all the same. “Squeeze” is about a serial killer with a penchant for liver and an ability to get into the victim’s room despite there being no obvious entry points. And if there’s something strange in your neighborhood, who you gonna call? Ghostbusters! Mulder and Scully!
What pushes this episode into horror territory is Doug Hutchison’s portrayal of Eugene Victor Tooms, the man (or, rather, mutant) suspected of the murders. His creepily detached performance is terrifying in its own right—but this is The X-Files, so of course there’s a paranormal element to the mystery, too. Tooms’s unnerving ability to squeeze himself through small spaces in the quest for livers—hey, mutants gotta eat too!—robbed me of the peace of mind usually provided by a firmly locked door. The eerie shots of his yellow eyes staring out from the darkness ensured that this sense of unease would burrow deep into my brain, where it remains to this day…
“The Host” (Season 2, Episode 2)

If the newspaper-and-bile nest created by Tooms in “Squeeze” wasn’t gross enough for you, then I present “The Host” for your viewing displeasure. A partially eaten body is pulled from the sewers of New Jersey but no one knows who or what did the chomping. Mulder initially believes he is being punished with this sewer-based assignment, but when Scully pulls a flukeworm out of the body, his Mulder-senses start tingling. Real-life parasitic worms are disgusting enough as it is and the scene where one is puked up in the shower is gag-inducing, but this episode is just getting started.
Mulder and Scully discover that the thing eating people in the sewers is a grotesque half-worm, half-human creature. Dubbed the Flukeman, it has a humanoid body but pale worm-like flesh and the circular fang-filled mouth of a flukeworm. The creature design of the Flukeman is fantastically repulsive and will leave you suspicious of drains and sewers for the rest of your life.
“Humbug” (Season 2, Episode 20)

“Humbug” is the first episode written by Darin Morgan, who was hired as a writer on the show after playing the Flukeman. Morgan, whose older brother Glen was already a writer and producer for The X-Files, infused his episodes with a satirical, but always affectionate, style of comedy. “Humbug” is the first episode that was hilariously self-aware but it still has some creepiness sprinkled throughout.
Over the course of 28 years, someone has been killing circus performers living in a community in Florida. Mulder insists, with his typical self-confidence, that the mysterious killer is the Fiji mermaid, a creature that Scully assures him has been debunked as nothing more than a P. T. Barnum hoax. While that’s never stopped him from somehow being right in the past, thankfully this is one of just a handful of episodes where he’s wrong.
The killer turns out to be former performer Lanny’s underdeveloped conjoined twin, Leonard, who can detach himself and crawl around. (And to Mulder’s credit this is how a theoretical half-monkey, half-fish would move around on land.) For years Leonard has been looking for another host while alcohol abuse has destroyed Lanny’s liver, but his attempts to latch onto people have killed them. Leonard is undeniably the stuff of nightmares, but the other sideshow performers provoke great conversations about how unfairly society treats those it deems weird or different. It’s surprisingly insightful, satirical, and just a little bit scary.
“Home” (Season 4, Episode 2)

The scariest episode of The X-Files is without a doubt “Home,” which was the only episode deemed so messed up that it aired with a TV-MA rating. It starts off dark, with a new-born baby being buried alive, and only gets darker from there. Some kids playing baseball find the baby (why did it have to be kids?!) and Mulder and Scully quickly suspect the three Peacock brothers who live in a rundown house nearby. Due to numerous birth defects, Scully concludes that the baby was the product of inbreeding, but the Peacock mother apparently died in a car crash a decade earlier. So what to do? Go snooping of course!
The Peacock brothers don’t appreciate the intrusion into their closely guarded world and enact revenge by brutally murdering the town’s sheriff and his wife as the ’50s love song “Wonderful! Wonderful!” plays in the background, which is purposefully discordant against the violence. (Johnny Mathis wouldn’t allow his version to be used—because, well, obvious reasons—so a sound-alike performed it.) The rotten cherry on top of this horrible sundae is the reveal that the Peacock mother is alive—stuffed underneath a bed and missing all of her limbs. There are some moments of gallows humor to break up the relentless grimness of the infanticide and incest, but even so “Home” remains the most disturbing episode of The X-Files.
“The Post-Modern Prometheus” (Season 5, Episode 5)

One of the great things about The X-Files is how well it can mold itself to different styles and this is perhaps most evident in “The Post-Modern Prometheus.” Shot in black and white, this episode is inspired stylistically and narratively by James Whale’s Frankenstein (1931). This gives the episode the old-school charm of a Universal classic monster movie but with a far more surreal edge, which makes everything feel like a bizarre dream.
Our FBI agents are called to a small town after a woman reports being knocked out with gas and impregnated by a “monster,” a creature the townspeople call The Great Mutato. It is discovered that The Great Mutato is the result of Dr. Pollidori’s genetic experiments, and like Mary Shelley’s Dr. Victor Frankenstein, he rejected his creation. Pollidori’s father secretly took Mutato in (yay!) and wanted to provide a companion for him, hence the whole impregnating unconscious women thing (nay!). This is obviously a big yikes, but the episode does attempt to redress the balance: Dr. Pollidori murders his father and is then arrested himself, so that’s something.
The whole thing ends with Mulder and Scully taking The Great Mutato to see Cher perform (after discovering his shrine to the actress/singer/icon—inspired by her role in the film Mask, the lonely outcast had formed a lifelong attachment to the performer). And what better way to end an episode? Sadly the real Cher declined to appear, a decision which she regretted after seeing the episode. Despite taking place in a weird comic book world which feels divorced from the reality of the overall show, Mulder and Scully dancing to Cher’s rendition of “Walking in Memphis” is one of their sweetest moments.
“Mulder and Scully Meet the Were-Monster” (Season 10, Episode 3)

For me, “Mulder and Scully Meet the Were-Monster” is the standout episode from the revival seasons. It’s another Darin Morgan creation and goes harder than ever in lovingly poking fun at the tropes the show is known for. It’s precisely the right amount of meta and is stuffed full of fun Easter eggs—ranging from Mulder wearing his infamous red Speedo to his ringtone being the show’s theme song.
Mulder is going through a mid-life crisis, lamenting that he’s already found every supernatural oddity and wondering if he’s wasted his life chasing false leads, when he’s pulled right back in—this time, by the appearance of a possible lizard person in Oregon. He thinks this monster might be a lizard version of a werewolf, but in a fun reversal it turns out that it’s actually a reptilian creature that was bitten by a human, not the other way round. Duchovny and Anderson are in top comedic form in this episode, as is comedian (and noted cryptozoology fan) Rhys Darby, whose performance as the lizard man is delightfully hilarious.
***
Have I missed out your favorite X-Files episode to watch around Halloween? Let me know in the comments below!
Lorna Wallace has a PhD in English Literature and is a lover of all things science fiction and horror. She lives in Scotland with her rescue greyhound, Misty.
War of the Coprophages is also a good addition.
In the funny not scary category I nominate “Bad Blood.”
“Die Hand Die Verletzt” for the an actually spooky episode.
‘Irresistible’ is one of the best and creepiest of all of the X-Files episodes IMHO. Although the villain is indeed human, that makes it all the creepier. The followup episode ‘Orison’ is okay, but they kinda jumped the shark with it. I even got the ‘Irresistible/Die Hand Die Verletzt VHS combo back in the day, since both episodes were excellently creepy.
“José Chung’s ‘From Outer Space'” is quite Halloweenish with its mummery; it’s also one of Darin Morgan’s handful of fantastic contributions (of which you’ve already included two) – It should be here!
I think my pre-teen brain and all the years that have passed in between have made a strange blend of “Squeeze” and “The Host” in my memory, but either one or the other of them (most likely both) scared young me so thoroughly that I could feel the effect for at least a decade to come yet (the only thing with a more profound impact were the Gentlemen from the episode “Hush” in “Buffy the Vampire Slayer”).
“Mulder and Scully Meet the Were-Monster” originally began life as a script for a Kolchak: the Night Stalker revival series that was cancelled before Morgan’s script could be used. As a nod to it’s origin, Guy Mann (the Were-Monster) is basically wearing a Kolchak costume. My favorite bit about all of Morgan’s X-File episodes is his digs at Mulder’s character (“…that ticking time bomb of insanity”)
“Die Hand…” is definitely in my top five. Mrs. Paddock is the kind of teacher any student should fear – and the kind of teacher I tried to emulate in my own career (without the human sacrifice element however).
Ice and Darkness Falls come to mind.
Definitely Bad Blood and along with Squeeze is Tooms
Have to second everyone mentioning Bad Blood. It’s imo the most hysterically funny “monster of the week” episode they ever made. I get the giggles just thinking about Luke Wilson’s front teeth.
Uh, yeah, thanks a lot for including the ENDING of each episode, even directly stating, ‘Everything ends by…’ WOW… Seriously… Does no one else have a problem with this…?
@12 Are you seriously upset by spoilers for a show that aired last century?
wiredog@13: Given that most of the people who read this site probably weren’t born in the last century, it’s not unreasonable to suppose that many of them haven’t actually seen this show, or at least all of the episodes.
Frankly, I’d be upset if somebody spoiled the ending of The Canterbury Tales or The Iliad, unless I were reading an analysis of the work or some such. Why is it surprising that people who have never read a particular book, attended a particular play, or seen a particular film or television show don’t want the ending revealed? The attitude that this is acceptable is the same reason I despise the people who put film trailers together: they insist on telling me the entire plot before I’ve seen the film, and I cannot fathom the thought processes of people who enjoy that.
Some of us just like to enjoy a surprise. Why is that so hard to understand?
We absolutely understand that not everyone wants to encounter spoilers, even when revisiting older shows, which is why a spoiler warning was included at the top of the article. Let’s move on.
The episode Home…. whew! I haven’t seen it, but the description of it reminds me of the horrors of the book Geek Love. *shudder*
My hubby and I just started watching the X Files, I’d only seen some of them back in the 90s and he even less, I don’t mind the spoilers, the beginning of the article said there would be spoilers, but I read on anyway like the wild fool I am! Also, I know by the time we see any of these, I’ll have forgotten any of those said spoilers.
“Clyde Bruckman’s Final Repose “, season 3, ep$. Fortune tellers being killed by a psychic psycho? The props are deliciously Halloweeny- crystal balls, tarot cards, and every stereotype of store-front psychic! Tongue-in-cheek fun, not really scary.
Hilariously, the drawing of the Fiji Mermaid that was shown on a menu in Humbug – rather than any of the circus performers or even Leonard – was what gave me night terrors for months as a child. I was perhaps 9 or 10 back then and regularly woke up screaming that that drawing was coming after me. XD It also made me not rewatch that episode until I was 36 and even then I only managed to look at it through my fingers. And that was after Tooms, the Fluke Man and Duane Barry, aliens and all else were creepy but fine even back then… love the ep, still regularly get the creeps when I watch it. :D
Some other faves of mine would be Ice, Darkness Falls, Quagmire, El Mundo Gira and Detour, all very good Halloween viewing as far as I’m concerned. :D
One of my favourite and most memorable episodes in the X Files was Arcadia, which, while it’s not specifically Halloween related, it has an incredibly scary monster of the week, and is an incredibly hilarious send-up of NIMBYism, worth watching just for that aspect of it. Also pretty funny to watch Mulder and Sculley pretend to be bright newlyweds :D