Aliens, ice worms, and smoking men, oh my!

"The X-Files" spent the early 1990s and 2000s scaring the crap out of anyone brave enough to watch it. The cases of Agents Fox Mulder (David Duchovny) and Dana Scully (Gillian Anderson) focus on the things that hide in the dark, causing the mysterious bumps you hear in the night. The pair regularly find themselves up against everything from government conspiracies to little green (or grey, according to Mulder) men, but any good and sufficiently weird sci-fi show has to have its monster of the week.

Monsters in "The X-Files" range from the absurd to the downright horrifying. If you are into that kind of thing, it's hard to pick a favorite from the show's long list of baddies, but one of them caused some real horror behind the scenes.

Eugene Victor Tooms, an immortal, liver-eating, contortionist serial killer is an "X-Files" fan-favorite, regularly topping lists of the show's best monsters ever. If you are an "X-Files" fan, that sentence doesn't sound weird at all. If you're not, strap in because it only gets stranger.

Naked Squeeze

Tooms originally appeared in the show's third episode and was one of the few characters to get a follow-up chapter. The character's ability to hide and hunt via small spaces and his need to consume a human organ is what makes him undeniably freaky. The actor behind the monster, Doug Hutchison, decided to up the creep factor even more and perform one scene completely naked.

Along with all of his other abnormal habits, Tooms hibernates in a cocoon of stomach bile and reemerges every 30 years to feed on human livers. Mulder and Scully find Tooms' lair and Mulder goes in after him, which ends with a naked Tooms chasing him through a small underground tunnel. The sequence is intense and creepy, but the story behind the scene might just outdo it.

Chris Carter, the show's creator, revealed the story behind the scene, saying:

"[Hutchison] wanted to shoot the whole thing naked, was naked on the set, and it caused a little bit of discomfort, which was good. I think it actually added to the scene. I think David was very nervous about being in a little, tiny, confined space with a naked man, to be honest. I think it made the scare, the creep all [the] more real."

It shouldn't surprise anyone that the man who thought all this eeriness up smiled at the memory of poor David Duchovny skittering away from a naked man covered in stomach bile. But, he's probably right — Duchovny's reaction during the scene was probably enhanced by all the naked awkwardness. I'm sure the "discomfort" on set that day made some people, including Duchovny, question their career choices, but it would result in one of the best episodes of the series and set the bar for what "X-Files" monsters should be.

Extracting Liver And Fear

Everyone is afraid of something. Children's fears often focus on the supernatural, the shadow in the closet, or the monster under the bed. Adults sometimes outgrow their fear of the paranormal, often growing more fearful of realistic concerns, such as disease and premature death. But what if we all saw the truth as kids? What if that shadow in the closet was real? What if the monster under the bed would eat your toes if they weren't under your blankets? "The X-Files" blends these childhood fears with adult rationalizations and anxieties. If the monster under the bed was in the show, for instance, he would suffer from a rare mutation that limits his sustenance to human toes.

Before "The X-Files," all I had to fear were things that couldn't exist in the real world. Even as a kid, I never believed in the creature under the bed or the shadow in the closet, but Mulder and Scully reminded me of the true monsters. There was no denying that humans were real and that some of them, like Tooms, were evil.

The first Tooms episode marks a shift in "The X-Files" that would become the show's quintessential monster of the week template, and it's the first time Mulder and Scully investigate something other than extraterrestrials or UFOs. Tooms expanded the world of Mulder and Scully beyond little green men and made younger viewers, like me, wonder what else they'd find hanging out in the shadows with the aliens. One answer is a human man with a muscle and bone structure that allows him to stretch his body to impossible lengths, which he uses to sneak into houses through air vents and chimneys, ripping livers from unsuspecting victims. I'm sure the aliens packed up their probes and left when this creep slinked up beside them in the dark.

Tooms, like all "X-Files" monsters, is a Smorgasbord of our worst childhood and adult fears. He is the monster who can hide in impossibly small spaces and consume body parts in the night, but he is also the human serial killer who attacks and kills you in your home for his own selfish reasons. He's a little something for everyone, young and old, that sticks with you long after the episode ends.

What Makes Tooms Terrifying

In Tooms' last scene, he is hiding inside an escalator shaft, where the naked chase happens. Mulder gets away, starts the stairs, and Tooms is crushed to death, but the damage to my childhood imagination was already done. "X-Files" monsters are like cockroaches — for every one you see them kill, there are a thousand more, and they are probably bigger and nastier. After Tooms, all of the series baddies would be new and interesting variations on this blend of human and monster. Other kids and adolescents at the time would embrace this nasty combination of freak and go on to create movies and tv series that show more of their ugly faces.

The Carter brand of creature can be found in popular sci-fi and mystery shows like "Supernatural" and "Bones." Both of these series had episodes that were homages to "The X-Files" case, "Home," where Mulder and Scully investigate a deformed inbred family. This episode was so disturbing it was banned from TV for three years. While the other shows did their best to imitate the same style of creep as "The X-Files," there really is no substitute for a screeching, distorted, limbless, Mrs. Peacock being pulled out from under her bed. Remember, she, like Tooms, is totally human, and both are often listed as two of the scariest suspects in the series. Humans are more disturbing than any supernatural creature Carter's sick mind could cook up.

So, keep your toes covered at night, always leave the hallway light on, and never assume you are alone. The truth may be out there, but the worst might be inside all of us.

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