10 Most Memorable ‘X-Files’ Monsters

Matthew Hadick

From the complex web of conspiracy that composes its narrative core, to Mulder and Scully‘s hot-and-cold romance, The X-Files has earned its place in the annals of classic science fiction as a deftly written masterpiece. Like most classics, The X-Files wears its spiritual influences on its sleeve, self-aware and demonstrably respectful of its place in the storied lineage of horror and sci-fi.

One of the more interesting ways the show pays tribute to classic sci-fi is through its “Monster of the Week” episodes, which function almost like short movies or horror procedurals in the sense that they rarely have an impact on the overarching narrative — they’re structured like mysteries and they tend to resolve by the episode’s conclusion. They also account for some of the most dread-inducing moments in the series. Like a group of trope-happy Dr. Frankensteins, the writers seemed to have had a lot of fun crafting their monsters, employing — and subverting — oft-used genre conventions to terrify viewers.

With the long-awaited return of The X-Files upon us, it’s time to revisit some of the most memorable creatures ever encountered by the X-Files unit. Here are 10 monsters that still keep fans up at night.

Eugene Victor Tooms


Season 1, Episode 2 – “Squeeze” / Season 1, Episode 20 – “Tooms
The first-ever “monster of the week,” Eugene Victor Tooms set the bar high. An ageless contortionist capable of fitting through any crevice, Tooms is a serial killer for whom conventional physical barriers aren’t an issue. When he’s not hibernating for upwards of 30 years in his “nest”, constructed from human bile and newspaper, he’s trolling college campuses and small towns for human livers, the likes of which he forcibly removes from his victims. Luckily, Tooms was fatally crushed beneath a moving escalator which, contortionist freak or not, had to hurt.

Parasitic Ice Worm


Season 1, Episode 8 – “Ice
The parasitic ice worm slithers and hooks its way deep inside the brain of a host organism, attaching itself to their hypothalamus. Of course, these little buggers don’t have peaceful intentions: they turn their hosts in murderous psychopaths, incapable of controlling their wrath. If the worm is extracted, it releases a poison into the host’s body, killing them instantly. In an episode based on John Carpenter’s classic science fiction thriller The Thing, the ice worms were enough to dismay a research expedition in Alaska, causing the paranoia-stricken team to kill themselves and each other.

Eve 9 and Eve 10


Season 1, Episode 10 – “Eve
While investigating the bizarre murder of two men at the exact same moment despite being 3,000 miles apart, Mulder and Scully find out that the victims’ daughters are identical. Soon, it becomes clear that this pair of seemingly innocent children actually committed the crimes, using the same gruesome technique: blood letting. When it’s revealed that the pair are clones — their murderous instincts indicative of a biogenetic glitch — you can’t help but realize that the pair haven’t made a single expression throughout the entire episode.

The Flukeman


Season 2, Episode 2 – “The Host
The Flukeman could be totally harmless, maybe even a nice guy who’s always fast with a really funny joke, but I don’t care. It might be shallow, but on looks alone, he’s one of the most terrifying creatures in the history of television. That said, there are a lot of perfectly acceptable, non-superficial reasons to fear this walking parasite. A science experiment gone awry, the Flukeman wanders the sewers looking for human bodies to embed its larvae into, which can’t be a pleasant experience for anyone involved. Buy a guy a drink first, why don’t you?



Season 2, Episode 20 – “Humbug
Yes, Leonard comes from an episode of The X-Files that’s supposed to be lighthearted and comedic, but there’s nothing funny about a deformed fetus living off the alcohol-soaked malnutrition of its twin brother. Leonard, originally thought to be a “Fiji Mermaid,” detaches from his brother every night to seek a new host by attempting to burrow in their stomach. I suppose he just wants to be loved — or something like that. Eventually, poor Leonard achieves his goal — kind of —by finding his way into the stomach of The Conundrum, who devours the deformed twin as a snack.

Clyde Bruckman


Season 3, Episode 4 – “Clyde Bruckman’s Final Repose
Clyde Bruckman isn’t scary because he poses a threat to the people around him. In fact, he helps Agents Scully and Mulder track down a murderer. Clyde Bruckman is so disturbingly memorable because the powers that make him helpful — the ability to tell when a person will die — also make his life a living hell. Bruckman is tormented by the image of his own body decomposing and eventually commits suicide to escape — and fulfill — the recurring nightmare.

Peacock Family


Season 4, Episode 2 – “Home
Oh, how the delightfully disfigured Peacock Family will haunt my dreams forever. “Home” is so viscerally disturbing that Fox found it necessary to air a viewer discretion advisory to warn viewers of its content. Just when you think the episode has reached its brutal climax, Mulder goes and looks under a bed to find the “matriarch” of the Peacock family, limbless and lying helplessly in a sled. As far as inbred murderers go, it doesn’t get much more brutal than this. It’s all too easy to forget that this originally aired all the way back in 1996.

Leonard Betts


Season 4, Episode 14 – “Leonard Betts
Leonard Betts, an alias used by an EMT named Albert Tanner, is a mutant who uses the cancer in others to regrow lost body parts, a strange power discovered after his head was severed in a car accident. There is nothing quite like seeing that disembodied head move during Scully’s autopsy or seeing Betts’ “fresh” noggin slowly rise from an iodine-filled bathtub. Betts also enjoys the distinction of being one of the only monsters to influence the overarching narrative: In their final confrontation, Betts reveals to Scully that she has cancer, setting into motion one of the series’ more substantial character arcs.

The Bark Creatures of the Everglades


Season 5, Episode 4 – “Detour
These bark-skinned creatures haunt the lush swamps of the Everglades, using their camouflage to gruesomely murder unsuspecting passers-by in an attempt to protect their territory. Mulder posits that they descend from the Spanish conquistadors who discovered the fountain of youth. This episode will have you scanning trees for a pair of the monsters’ demonic red eyes.

Rogue A.I.


Season 5, Episode 11 – “Kill Switch
In an episode written by William Gibson, the science fiction writer credited with coining the term cyberpunk, a sophisticated A.I. goes rogue and murders its creator. The A.I. uses the Internet to gain as much knowledge as possible, going as far as constructing physical devices that constrain human beings to download their memories and brain patterns.  It’s a clever subversion of a classic Asimovian idea that makes for a chilling mystery, which is to be expected from the celebrated progenitor of cyberpunk.

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