For 10 seasons, The X-Files has taken viewers to many dark and mysterious places around the world - and beyond. “The Truth is Out There” is the mantra for the series and for FBI Special Agent Fox Mulder (David Duchovny) as his belief in the supernatural and the unexplained led him to question everything. While the overarching storylines of the series dealt with the abduction of Mulder’s sister in connection to the existence of extraterrestrials, governments conspiracies and human testing, many cases had different terrors.

The meat and potatoes of the show during the prime years were the “Monster-of-the-Week” episodes. These mostly standalone cases played out like mini-horror films as Mulder, along with his partner, FBI Special Agent Dana Scully (Gillian Anderson), encountered disturbing and downright evil characters and entities. Harkening back to predecessors like Kolchak: The Night Stalker and The Twilight Zone, these The X-Files stories expertly weaved into the plot terror and suspense, while simultaneously creating nightmare inducing monsters.

While the series has its share of serial killers and psychos, we narrowed are search of memorable monsters to include mutants, creatures, the supernaturally inclined and the clawed and fanged. Here are the 15 Most Disturbing X-Files Monsters.

15. THE KINDRED (Season 1, Episode 14)

Our first selection is a grab-bag of strange and scary elements crammed together to form a community that you definitely don’t want to cross. Think Children of the Corn mixed with Invasion of the Body Snatchers and a dash of gender swapping. A little convoluted to say the least.

In the episode titled “Gender Bender”, agents Mulder and Scully are investigating a series of sexually-charged murders that leads them to an Amish-type, closed community with a boatload of secrets. The killer the agents are looking for uses super strong pheromones as the weapon of choice, with all signs pointing to him or her being a member of the community which calls itself The Kindred.

While snooping around the village, Mulder learns that this mysterious group is a cult of some kind complete with strange rituals that involve burying members in white clay and the ability to change their gender. That handy trick along with The Kindred’s ability to seduce anyone they rub their hands with, has given their rogue member the means to kill and escape. The quiet and eerie Kindred may look Amish with their traditional garb, but it turns the group are a race from another planet. Before Mulder and Scully can move in on them, The Kindred disappear leaving behind a crop-circle where their home once stood.

14. SAMUEL ABOAH (Season 4, Episode 3)

It’s easy to spot a victim of Samuel Aboah, as the bodies are devoid of skin pigmentation. Like the name of the episode, Samuel Aboah is said to be a “Teliko”, a-sort-of vampire found in African lore with the ability to squeeze into tiny spaces similar to Eugene Victor Tooms (which you’ll learn more of in this list). The West African Samuel travels to America and hunts down African-American men using poison darts, sucking out their pituitary glands. The white corpses are the end result.

It may not be directly mentioned but the influence of the Voodoo religion and the Haitian interpretation of a zombie is prominent throughout. Just looking at Samuel’s appearance with the red eyes and pasty white skin color and hair, draws comparisons to past genre films and books. As is the case with many X-Files monsters, Samuel commits his vicious acts out of necessity, having to feed off others in order to replenish his genes. Regardless of his reason, having Aboah appear from the shadows to treat you like a tasty snack is a scary sight for anyone.

13. THE BEGGAR MAN (Season 8, Episode 10)

This is the winner for the most disgusting and cringe inducing premise for a monster. With Fox Mulder out of the picture in Season 8, Scully and her new partner John Doggett (Robert Patrick) are assigned a case with a body that’s been drained of blood, with massive internal stomach damage. The culprit behind the murder ends up being a legless Indian mystic played by the Oompa-Loompa himself, Deep Roy. Moving around on a cart begging for money, the diminutive nightmare has the ability to hide and live inside another person’s stomach, thereby controlling the body like a human puppet. Eek!

How The Beggar Man enters a body is revolting enough. Let’s just say it’s not through the mouth. If a little person living in your stomach doesn’t freak you out, then maybe the sight of The Beggar Man moving around in his squeaky cart will push you over the edge. Those squeaky wheels are his trademark sound, hearing him before you see him attack.

12. ROB ROBERTS (Season 7, Episode 3)

Looking like a character from Alien Nation, Rob Roberts is your mild manner mutant that subsists on human brains in order to live. Unlike a mindless zombie that craves the taste of what’s inside our cranium, Rob is fully aware of what he’s doing but needs to feed. He may not want to be a monster but it’s what he is.

In the episode titled “Hungry” we meet Rob, who is trying to pass himself off as a regular looking schmoe working at a drive thru restaurant. What do we get if we take away his hair, eyebrows, ears, contact lenses and false teeth? Well, we’re left with Rob’s true visage which is a disgusting bald mutant with midnight black eyes and piranha-like teeth made to shred into brains! Even though he tries to suppress his taste for brains with prescriptions and medicines, his homicidal tendencies overtake him thereby putting on Mulder and Scully’s radar. We wouldn’t want to have dinner with the guy, but you can’t help but feel sorry for him especially at the end where he forces the agents to kill him. His last words were, “I can’t be something I’m not.”

11. CHINGA THE DOLL (Season 5, Episode 10)

Next to clowns, there’s nothing more disturbing in a horror film (or real life) than a doll. From Chucky, to Billy and Annabelle, the horror landscape is littered with these sinister and malevolent playthings. Not to be outdone, The X-Files offered up Chinga, an antique doll infused with evil powers and witchcraft. Belonging to little Polly, Chinga would say “I want to play” which would spark death and terror using the young girl’s demands and wishes.

While on vacation, Scully happens upon the small New England coastal town whose residents are unexplainably doing harm to themselves like gouging their eyes. Turns out they are living in fear of Polly and her doll which is a spin on the classic The Twilight Zone episode, “It’s a Good Life.” To make the doll and story that much scarier, horror maestro Stephen King co-wrote the episode with Chris Carter. King infused the script with his trademark scares, helping the episode standout as one of the best standalone horror entries of the series. Even though Chinga loses her grip on Polly and is burned, the evil doll is discovered in the last scene telling its new owner, “I want to play.”

10. PHYLLIS PADDOCK (Season 2, Episode 14)

Over the seasons, The X-Files has explored the themes of faith and religion through the characters of Mulder and Scully. Every year viewers would be guaranteed to find a couple of episodes revolving around the eternal battle between good and evil. God vs The Devil. In season 2, The Prince of Darkness himself appears as the antagonist in the episode titled “Die Hand Die Verletzt.” He doesn’t come in the form of massive winged monster or an intimidating demon sporting large horns. No, the form the Devil takes is that of an unassuming substitute teacher. Phyllis Paddock is literally the substitute teacher from hell.

Mulder and Scully are in over their heads. They show up at a high school where the mutilated bodies of teens have been found and linked to satanic worship. From frogs falling from the sky, to light emanating behind doors, things are weird. While all signs point to the faculty members/Satanists being the killers, it turns out that little old Phyllis Paddock is the murderer. Satan has taken human form to clean up the mess by his followers and to create some chaos of his own. After taking care of business, Mrs. Paddock disappears only leaving behind a sinister message: “Goodbye. It’s been nice working with you.”

9. WEREWOLF/LYCANTHROPE (Season 1, Episode 19)

The X-Files does a good job of incorporating classic monsters such as vampires and zombies into their mythology. One underserved creature the series spotlighted was our furry friend, the werewolf. In the episode “Shapes”, Mulder and Scully head to a Native American reservation to investigate the murder of a man. There they discover that the suspect they’re looking for and reports of a monster terrorizing the area, might be one in the same.

The writers delved into Native American beliefs and legends such as the Wendigo, to build their plot. While the Native American angle didn’t really bring anything new to the table, the episode was a solid hour of werewolf scares for fans of the beast. As the events play out, Mulder naturally believes that they should be looking for a shapeshifting lycanthrope, while Scully counters with psychotic delusions as the more plausible cause.

Influenced by An American Werewolf in London and The Howling, the werewolf suit and special effects were pretty solid considering it was for network TV. The transformation itself consisted of actor Ty Miller screaming as he spouted hair, fangs, and had his skin ripped. The last thing you’d want is to be stuck in a cabin with someone going through those changes!

8. EVE 9 & 10 (Season 1, Episode 11)

You knew at a certain point we would have creepy, evil kids on this list and this is a two for one special. Cut from the same cloth as the Grady twins from The Shining, Eve 9 & 10 are cloned for pure evil. Instead of the matching blue dresses the Grady’s wear, these clone girls sport matching red jackets. The girls don’t say much but they have the “evil eye” thing down pat, as they hatch deadly plans to murder and destroy those who land on their bad side.

In the episode titled “Eve” the girls are part of a cloning super-soldier project gone bad, that has seen several other incarnations of Eve before. Past versions have been destroyed, institutionalized, or are on the run like the adult Eve 7 who went ahead and created 9 & 10. They may look like angels but these kiddies really hammer home the horror trope of twins and evil. Raised by different families we discover that both girls killed their respective fathers, then killed Eve 7, and finally tried to take out Mulder and Scully by poisoning them. Babysitting kids with homicidal tendencies can be hazardous to your health.

7. THE GREAT MUTATO (Season 5, Episode 5)

This episode is one of the weirdest and quirkiest X-Files chapters you’ll ever see and that’s saying a lot considering the mythology of the series. A smorgasbord of odd from being shot in black-and-white; to the Universal Monsters-like hook; a Jerry Springer cameo; and having Cher play a large part in the plot.

While Cher doesn’t directly appear, her presence is felt throughout as The Great Mutato is a huge fan of hers. Titled “The Post-Modern Prometheus”, The Great Mutato is the monster of the episode: a deformed, misunderstood figure that’s a cross between The Elephant Man and Frankenstein. While the tone of the episode is comedic including John O’Hurley playing a mad scientist and Mulder and Scully sharing a dance, the subtext is really dark. Looking past The Great Mutato’s ugly appearance, what makes him really a monster is that he rapes women. The writers tend to gloss over the consent issues but while looking for love, Mutato impregnates drugged women around town. Yeah, that’s pretty messed up.

It’s hard to cheer for a monster rapist but the ending perfectly caps off this unusual episode. Mulder and Scully take Mutato to see Cher (an impersonator), with the monster basking in her song “Walking in Memphis.”

6. LEONARD (Season 2, Episode 20)

The episode titled “Humbug” is one of the most loved and best reviewed episodes ever for the series as viewers are introduced to group of eccentric sideshow performers. In the episode, Mulder and Scully head to a community of former circus performers where murders have been occurring. There they meet over-the-top characters like the human blockhead and Conundrum. The humor and tone of the episode is on par with Twin Peaks even including alumn Michael J. Anderson. While there are many funny scenes, there’s also a heavy dose of scares and frights once we discover what's behind the murders.

Straight out of the cult horror film Basket Case, the killer turns out being a grotesque, deformed conjoined twin brother that goes by the name Leonard. The Kuato-looking (Total Recall) tiny freak is able to detach himself from his normal sized brother Lanny, to go off and attack residents. Those attack and chase scenes are standard horror movie fodder as we get the POV of Leonard crawling on the floor and hiding in the dark as he stalks his victims. Amongst this community of freaks, Leonard is just a nasty creature, the ultimate personification of the darkness we all carry.

5. BARK CREATURES (Season 5, Episode 4)

We can only tread on Mother Nature for so long until she takes a stand and sends forest creatures to repel us. If you don’t think a tree creature sounds scary, just wait till you watch this episode titled “Detour.” In it we find Mulder and Scully on a road trip to an FBI conference, where they come upon a police roadblock in the woods. Turns out that with a recent development boom and construction in the area, people have been suddenly disappearing. With no bodies to show for or signs of what type of animal is behind the attacks, Mulder suspects something supernatural.

While the humanoid monsters don’t have an official name, fans refer to them as bark creatures for their bark-like skin. The red-eyed monsters look like Swamp Thing but also have the ability to camouflage into their surroundings ala the Predator. Whether a mutation or simply an unknown animal, what they are is never really explained. At the end of the episode however, Mulder tries to take a stab by connecting them to Ponce de Leon and The Fountain of Youth. His theory that they’re Spanish conquistadores that have transformed into the bark creatures.

4. LEONARD BETTS (Season 4, Episode 12)

Veteran character actor Paul McCrane isn’t a stranger to playing a grotesque role with nasty skin issues. In 1987’s Robocop he played street thug Emil M. Antonowsky, who meets his demise in a disgusting way. Getting dumped into a barrel of toxic waste, McCrane’s body dissolves as he’s then turned into chunks of meat after getting run over by a car.

Playing the title character in the episode “Leonard Betts”, McCrane plays a cancer-eating mutant that can regenerate severed limbs and even create a duplicate body. Betts’ transformations are gross because his flesh is raw and slimy, leaving him somewhere between a zombie and a severe burned victim. When not looking like a monster, Leonard is an EMT paramedic with the ability to detect illnesses in patients. That handy skill allows him to find those that have cancer so that he can remove and feed on that tumor.

Not only was the episode a great “Monster-of-the-Week” but it hit two key milestones for the show. First, it was the most-watched episode of The X-Files ever, in large part due to it airing after Super Bowl 31. Secondly, in the episode’s final moments after Scully survives an attack by Betts, we discover that she has cancer which sparks a large story arc for her.

3. THE FLUKEMAN (Season 2, Episode 2)

When you think X-Files monsters, 9 times out of 10 Flukeman is the creature that comes to mind. The disgusting, pasty white parasite creature is a good old fashion monster, something you’d find in a B-horror movie. In the episode “The Host”, we learn that the mutated giant flatworm is a side effect of the Chernobyl nuclear disaster, making its way from a Russian freighter down to the New Jersey sewer system. Once underground, Flukeman attacks city workers, biting and infecting them which causes Mulder and Scully to take the case.

Toby Lindala and the rest of the special effects crew did an amazing job designing probably the most memorable and iconic creature from the series. Portrayed by staff writer Darin Morgan, the monster worm with a humanoid appearance, has a terrifying suction-like fanged mouth where it would bite and pass along its larvae. The scene where Flukeman gets caught in a transparent pipe is creepy and had viewers checking their toilets every time they’d use the bathroom. The claustrophobic sets along with the amazing make-up effects, led to “The Host” being praised as one of the best standalone episodes of the series.

2. EUGENE VICTOR TOOMS (Season 1, Episodes 3 & 21)

The perfect marriage of role and actor as both bring the creepy factor. Before actor Doug Hutchison was a tabloid staple with his made-for-TV love life, he played the role of Eugene Victor Tooms, a quiet man with genetic abilities to contort and elongate his body similar to Stretch Armstrong. Looking like Ted Bundy with a psychotic state to match, this mutant freak would hibernate for periods of thirty years only to wake up and murder to satisfy his hunger for human livers.

Tooms is special in X-Files lore as the character was the focal point of 2 episodes during the first season. The first was “Squeeze” which is also distinct for being the first “Monster-of-the-Week” show. In it Mulder and Scully investigate a rash of murders where the victims are missing livers, with each crime scene lacking entry points. Later in the season in the episode “Tooms”, the mutant is released on parole with the agents giving chase once again.

Doug’s brilliant performance was aided by his yellow eyes and special effects showing his body squeezing into a chimney, dog door and window crack. Just needing a small space to get to his victims is what made Tooms terrifying. Wherever they hid they weren’t safe.

1. THE PEACOCK FAMILY (Season 4, Episode 2)

When you get banned from television, that pretty much guarantees you the number one spot on this list. Going beyond the world of The X-Files, you probably won’t be able to find an hour of television as controversial, gruesome and creepy as this episode titled “Home.” After its original air date in 1996, Fox banned the episode from re-airing, giving it an even more taboo label. It was also the first network episode ever to receive a TV-MA rating.

In the show we meet the murderous Peacock family, a deformed, backwoods clan that’s something out of The Hills Have Eyes. Not only do they look like monsters with misshaped and ghoulish features but once we discover the family secret, you can’t help but cringe and be grossed out. Mrs. Peacock and her three sons have been partaking in inbreeding, a family tradition in order to keep the bloodline pure. That’s something that would even freak out Mrs. Voorhees and Jason. Just as uncomfortable is the state in which we find Mrs. Peacock. Mulder and Scully discover her under a bed to see that she’s a quadruple amputee on a rollout sled that is fed regurgitated food. Yikes!

We warn you to not watch this episode alone but if you do, you’ll never be able to hear “Wonderful, Wonderful” by Johnny Mathis the same again.