What scares you? Like, really, really scares you? I'm talking the proper frightening stuff. Those things that drive you to the point of not being able to go to sleep because of the thing that's absolutely, 100% totally staring at you from the corner of the room. Demogorgons, boogeymen, err... hockey-mask-wearing psychopaths, or perhaps, dolls painted to look like satan's minions? Or maybe it's a more insidious, subtle fear the fear that everything and everyone has a secret, and things aren't always what they seem?
No matter what gives you the heebie-jeebies, there's a horror movie ready to totally exploit those fears and run a perfectly good pair of underpants. This list celebrates the 25 greatest the genre has to offer. And that prickling sensation on the back of your neck, the one that says you're being watched? That's nothing. Don't worry about it.
25. A Nightmare on Elm Street (1984)
The movie: Wes Craven's iconic slasher takes the one place on Earth you're meant to be safest - tucked up under your bed covers - and makes it deeply unsafe by inventing a killer who attacks teenagers in their dreams. The scarred-up, knife-fingered Freddy Krueger (Robert Englund) is one of horrors scariest villains.
Why it's scary: The sweaty, gasping sensation of waking up from a truly scary nightmare is familiar to everyone, so the idea of a monster that actually uses nightmares to kill you in your sleep is a haunting one. Plus the nightmare conceit gave Craven and co. complete freedom to dream up utterly horrible kills.
24. The Babadook (2014)
The movie: Already struggling to cope with her difficult child, grieving widow Amelia (Essie Davis) adds to her troubles when she reads a mysterious pop-up book called Mister Babadook. Is there a monster lurking in her house? Or is it just a convenient scapegoat for her own inner demons?
Why it's scary: The Babadook is a harrowing tale about depression and grief. And while there are many, many horror movies about mothers and children, this might be the only one that will have you shrieking at the site of a pale bloke in a hat.
23. Ringu (1998)
The movie: Journalist Reiko Asakawa (Nanako Matsushima) is investigating a story about a cursed videotape and in the process, manages not only to watch it herself but to let her ex-husband and young child watch it, too. The idea of a haunted VHS tape is a brilliant one, and the climactic scene where the vengeful ghost finally makes her entrance is pure nightmare fuel.
Why it's scary: The cursed video concept suggests that not only are the characters in the film in danger but that you, the audience at home, are also in line to meet a sticky end. Yikes.
22. Cabin In The Woods (2012)
The movie: The generic title is intentional. The Cabin In The Woods is a horror movie about horror movies; right from the beginning, it's clear that something weird is going on as shadowy government types follow a group of kids heading off to, er, a cabin in the woods. It's beyond post-modern. It completely deconstructs the horror genre, taking it apart brick-by-brick before putting it back together again in a smart new shape.
Why it's scary: Recognising the manipulations that lead to familiar horror tropes supplies a fair few frights, but the real terror begins when those big lift doors open...
21. Scream (1996)
The movie: Wes Craven resurrected the slasher genre with this cheekily post-modern effort in the mid-90s. It ticks all the usual boxes, as a teenage girl and her friends are stalked by a masked killer, but these teens grew up watching movies and their ability to remember the rules will make the difference between living and dying.
Why it's scary: Scream works as a straightforward slasher in its own right, so even if you're not enough of a genre nut to spot all the references and homages, it's still terrifying. Someone calling you from outside the house? Yeah, that never stops being creepy.
20. The Haunting (1963)
The movie: Houses don't come much more haunted than Hill House. When a group of paranormal investigators and psychics go to investigate the houses weirdnesses, they're tormented both by the house's architectural quirks and the strange noises it makes after dark.
Why it's scary: Adapted from Shirley Jackson's novel, The Haunting's scares are low-key, but it's the atmosphere that stays with you long after the credits have rolled. Forget the turgid and terrible 1999 remake, and stick with this if you're after a proper night of terror. And insomnia.
19. The Evil Dead (1981)
The movie: One of the original video nasties, The Evil Dead sees a group of friends - led by Bruce Campbell's Ash - head out to a cabin in the woods for spring break, only to unwisely crack open the creepy Naturon Demonto and awaken evil spirits. Cue demonic giggling and plenty of gore.
Why it's scary: Shot on a shoestring budget with an inexperienced cast and crew, The Evil Dead has loads of energy and enthusiasm towards making you utterly terrified of trees.
18. Alien (1979)
The movie: Arguably one of the greatest science fiction movies ever made is also one of the greatest horror movies, as director Ridley Scott sends the crew of the Nostromo off to investigate a distress call from an abandoned alien spaceship as innocently as any gang of hormonal teenagers headed off to a remote cabin in the woods.
Why it's scary: There's nowhere more horribly isolated than a spaceship light years away from home. And Giger's alien is as terrifying a monster as you could wish for.
17. The Innocents (1961)
The movie: Creepy kids strike again! Miles (Martin Stephens) and Flora (Pamela Franklin) are the charges of Miss Giddens (Deborah Kerr), a governess working at a huge country estate. Their guardian has asked her never to trouble him with their problems, so when they start misbehaving and talking to ghosts, it's left to Miss Giddens to figure out what's going on.
Why it's scary: Is it scarier if the ghosts are real, or not? It's a tough call.
16. The Cabinet Of Dr Caligari (1920)
The movie: What's inside Caligari's cabinet? That'd be Cesare (Conrad Veidt), a sleepwalker who performs tricks on command. And also murders on command. The framing device makes the main plot of the movie, where Cesare is sent to kill a beautiful girl but cant bring himself to, into nonsense, but it's all so eerie and otherworldy it barely matters if it makes sense.
Why it's great: It's the ultimate German Expressionist movie, all canted angles and elaborately painted sets. Creepy and beautiful, nothing else looks like this movie.