Since 1993, Chris Carter's The X-Files has captivated audiences with tales of conspiracies and the supernatural. FBI Agents Mulder and Scully have traveled all around the country, investigating the weirdest and most unsolvable cases the government can throw at them. From ghosts to aliens and all the monsters in between, these two have tackled everything around the dark corners of the United States.

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Over its eleven-season run, The X-Files has produced some of the creepiest characters and foes for these two agents to confront. Killer kids, mutants, and serial killers abound their paranormal adventures. Looking back across the series, here are the ten creepiest characters ever to come out of the show.

Chinga

Chinga the doll sits in a chair in The X-Files

Before Annabelle was terrorizing audiences in horror series The Conjuring, The X-Files had their very own creepy murderous doll. Season Five episode "Chinga" followed Mulder and Scully as they investigated a series of murders connected to possible witchcraft. Soon, they discover though that the real culprit is none other than a possessed doll named Chinga.

Maybe Chinga just seems like a doll to some, but some of us understand that these toys are not to be trusted. Her cold dead face is responsible for the deaths of many, and her recovery at the end of the episode (even after being burnt to a crisp) means she could turn up at any minute.

Eve 9 and Eve 10

What's scarier than creepy dolls? Creepy kids, of course! Whether it's the Twins from The Shining or Carol Anne in Poltergeist, horror has always capitalized on the trend of terrifying children. The X-Files is no different. In the Season One story "Eve," Mulder and Scully have a run-in with two very creepy twins.

It turns out that Mulder and Scully uncover a secret cloning project, resulting in clones with hyper-intelligence, super strength, and an affinity for murder. These two girls, Eve 9 & 10, might seem like any normal girls, but in reality, they are a pair of evil geniuses.

Leonard

In the second season, Mulder and Scully explored a harrowing sort of carnival attraction. Tattooed bodies, bearded women, and conjoined twins were abundant in "Humbug." Though the show had many oddities, one character in particular would make anyone's skin crawl.

Leonard, the twin of a hotel clerk, is one of the most grotesque monsters of the whole show. Searching for an alternative host to Lanny, Leonard goes on a rampage. He is even mistaken for the Fiji mermaid. Both in design and concept, the whole idea is nauseating.

Phyllis H. Paddock

While The X-Files is primarily a show about alien cover-ups, it had its fair share of supernatural episodes as well. "Die Hand Die Verletzt" for example, was one of the best in the bunch. Researching the ritualistic death of a young boy, Mulder and Scully uncover a Satanic PTA cover-up at the boy's school. Little do they know that an even greater presence is right nearby, in the form of the substitute teacher Phyllis Paddock.

You can't get much creepier than a literal demon. It is not fully explained whether Paddock was the embodiment of the demon Azazel or possessed by the demon, but either way, her presence is frightening. Though Paddock turned out to be assisting the two agents in their investigation of the cult, her powers and abilities were creepy nonetheless.

Leonard Betts

Leonard Betts had to be included in this list. The most-watched episode of the entire series, "Leonard Betts" also has one of the strangest premises of the whole show. A paramedic nurse who has cancer is accidentally decapitated. Though headless, he rises from the morgue, killing an attendant and escaping. Betts becomes a murderous monster, bent on consuming any cancerous cells he can find.

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Leonard boasts some of the best body horror elements of the whole series. He is horrifying to look at, and the process of regrowth is equally terrible. From a conceptual standpoint and execution, Leonard Betts is one of the creepiest and best villains Mulder and Scully investigate.

Luther Lee Boggs

While many characters in the world of The X-Files are creepy due to their villainy, some are more subtle. When it comes to unsettling characters, Luter Lee Boggs certainly fits the bill. After the death of her father, Scully assists Mulder in the investigation of a kidnapper.

Utilizing the skills of a proclaimed psychic on death row, they attempt to gain more clues. What Scully didn't expect was for Boggs to channel the spirit of her recently-deceased father. Brad Dourif's performance is beyond creepy. Though never gruesome, the uncanny ability with which he channels this psychic is beyond unsettling.

Flukeman

While some might fear alligators in the sewer systems, Mulder found something far worse in the bowels of New Jersey. In the episode "The Host," Mulder finds evidence that a parasitic primate-like beast is living in the sewers of the Garden State. This is certainly the single creepiest make-up design of the entire series.

The Flukeman, a play on words of the parasitic flukeworm, is a humanoid with a sucker-like mouth. Actually a mutated human, the Flukeman arrived in the states via a Russian vessel. it escaped and traveled via the sewage system.

The Peacock Family

"Home" is what happens when The X-Files delves into folk horror. This episode finds the pair investigating a family in the rural Pennsylvania countryside who have possibly murdered an infant. This family is the Peacocks, and they're a bit too close for comfort.

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This bunch makes The Texas Chainsaw Massacre family look tame. Their design is beyond unsettling, and their murderous acts are incredibly disturbing. These characters are creepier than most because they are far more realistic. No ghosts or aliens are to be found, just 'regular' folk that you might find at the end of an eerie dirt road.

Donald Pfaster

Like the Peacock family, Donald Pfaster is equally scary because he is steeped in reality. A serial killer, Pfaster appears in two episodes: "Irresistible" and "Orison." Pfaster worked at a funeral home, and would collect hair and fingernails as treasures.

Eventually, he turned to live victims and obsessed over none other than Scully. Unlike a lot of the scares from these other creepy characters, Pfaster is anything but entertaining. He is in no way a fun sort of scare, instead embodying some of the darkest corners of the human psyche.

Eugene Victor Tooms

There is no creepier character in all of The X-Files than Eugene Victor Tooms. A recurring foe for Mulder and Scully, Tooms appeared in two separate stories throughout the series. Tooms had the uncanny ability to squeeze through any opening, condensing his physical form as small as possible.

As a mutated serial killer, Tooms would kill constantly to harness sustenance from the livers of his victims. This would allow him to hibernate for up to thirty or so years. While he might not be disturbing in broad daylight, it's when his disturbingly bright yellow eyes peer through vents that you realize the full scope of his horror. Tooms could literally be anywhere, at any time, in any form.

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