The Gentleman may have only appeared in one episode of Buffy The Vampire Slayer, but these well-dressed monsters are more memorable than most of the show's bigger multi-arc villains. Their floaty gait and toothy smiles are enough to cause nightmares, but it's their ability to keep their victims from making any sound that makes them truly terrifying.

Watch It On: Netflix

The great irony of "Home" is that the scariest episode of The X-Files isn't about anything supernatural. For a show dedicated to extra-terrestrial life and the paranormal, "Home" shows that there's nothing scarier than human nature. This episode will change the way you look at beds and what lies beneath them.

Watch It On: Hulu

Doctor Who has never been afraid to make people afraid, and episodes like "Blink" and "Midnight" from the Tenth Doctor era are the stuff of Doctor Who legend, but this Twelfth Doctor episode has both of those beat. "Listen" proves that the scariest thing of all is fear itself.

Watch It On: Amazon Prime

Over the course of its 13 seasons, Supernatural eventually left its monster-of-the-week approach on the back burner for the sake of its larger Heaven vs. Hell narrative. However, Supernatural has proven that when it wants to go full-on scary, it can produce an episode as horrifying as "Family Remains." If you've ever been concerned by a scratching or a thumping sound coming from behind your walls, this episode may hit a little too close to home.

Watch It On: Netflix

Black Mirror is known for being one of the most fear-inducing series of television, but there's no episode scarier that Season 4's "USS Callister." While the show has gone full-on horror in other episodes like "Playtest" and "Metalhead," the physical horrors and existential dread of "USS Callister" make this episode of Black Mirror far and away the scariest.

Watch It On: Netflix

Imagine if a child's every wish came true. It sounds like a nice thought, until you remember that children are often temperamental and don't always take to caring about what happens to other people. In this Twilight Zone classic, a young boy forces a town to follow his every whim, or else they are banished to an otherworldly "cornfield." The Twilight Zone may be over half a century old, but these scares stand the test of time.

Watch It On: Amazon Prime

Twin Peaks can go from a goofy procedural show from supernatural horror in a matter of minutes, but it never gets scarier than "Episode 14." A shocking revelation about Leland Palmer leads to a recreation of Laura Palmer's murder and and the death of Maddy Ferguson, combining discordant music and otherworldly lighting cues that one could only see on Twin Peaks.

Watch It On: Netflix

While the original Twin Peaks has terrifying moments pop up every few episodes, Twin Peaks: The Return features a brain-searing image of extreme fear at least two or three times an episode. While the entire series will unsettle even the most scare-immune viewer, "Episode 8" pushes the entire medium of television to become the most surreal, unnerving episode of television ever made. You'll shudder the next time someone asks if you've "got a light."

Watch It On: Showtime

Whether you're terrified of haunted houses, asylums, witches, vampires, carnivals, serial killers, cults, clowns, or reality television, American Horror Story has something that will have every horror fan reaching for the pause button at one point or another. The anthology series has left no stone unturned when it comes to common fears that they can add buckets blood and some unforgettable body horror to.

Watch It On: Netflix, Hulu

The German-imported Netflix original may not feature any monsters, but the series is as scary as they come. What the series lacks in monsters is makes up for in mystery, and will make you second guess ever walking into a mysterious cave in the forest.

Watch It On: Netflix

What if that television show from when you were a kid wasn't real? What if the haunted house didn't end when you left? What if a human man was made out of just teeth? Channel Zero asks all of these questions, and none of the answers are pleasant. This series based on Creepypastas, the internet version of a campfire story, combines grotesque imagery with uncertain realities to create unforgettable stories.

Watch It On: Syfy

The Americans is a spy drama, but that doesn't keep it from going to some horrifying places. One scene in the Season 3 episode "Baggage" features a scene so gruesome that other horror series could only wish to create something so memorable. If you've ever looked at a suitcase and wondered, "Could someone fit a body in there," The Americans shows that the answer is "not easily."

Watch It On: Amazon Prime

Hannibal is one of the most horrifying, hypnotic, hard-to-watch series ever made. It's also beautiful, engaging, and exciting. Over the course of three seasons, Hannibal takes apart and reassembles the human body in every way imaginable, making an art out of destroying (and sometimes consuming) human. Human bodies are transformed into angels, totem poles, and giant eyeballs throughout the show and it's hard to look at but even harder to turn away from. You simply won't believe that this show aired on network television.

Watch It On: Amazon Prime

There are two words that can strike absolute terror and second-hand remorse into the heart of every Office fan — "Scott's Tots." While The Office is a comedy series with little interest in blood and gore, "Scott's Tots" features a kind of social horror that makes the episode nearly impossible to watch. The episode is so difficult to get through, that there is an entire subreddit dedicated to those who "Cannot Watch 'Scott's Tots.'" While other horror series may dream of getting their audience to turn away and stop watching, The Office pulled it off.

Watch It On: Netflix