What Women Want, starring Mel Gibson. Nothing has ever frightened me so much as the idea of hearing women's thoughts. I can't imagine the horror that would be in real life.

I don't know what I would consider "THE" scariest horror movie that's a pretty subjective question depending on the viewer/audience, but I can list a few which immediately stand out to me, and aren't on the usual top ten lists, such as "The Exorcist", "Halloween", "Nightmare on Elm St", blah, blah, and blah.

1. "Threads" one of the scariest, most chilling nuke/post-apocalyptic movies ever made. Truly bleak & terrifying.
2. "Rosemary's Baby" this one does often make the usual lists, but it's very unique, and one of the best unnerving conspiratorial horror movies out there.
3. "The Parallax View" Similar to above, but not technically a "horror" movie. It's more of a political conspiracy movie, and is REALLY creepy.
4. "Fragment of Fear" somewhat (undeservedly) obscure, but worth hunting down. really spooky psychological horror movie, with no straight answers, and will leave you thinking about it long after it's over.

Those are just a few offbeat chillers that came to mind. Just wanted to list some great overlooked titles which aren't often discussed.

Don't know but any movie that pushes gore and relies solely on jump scares can't be in the top.

I'm a sucker for Japanese/South Korean horror, so I hope you don't mind subtitles, but I'll add a Western one into the lot (respect the dates because remakes are always worse):

One Missed Call (2003) will give you nightmares.

The Wailing (2016) will fuck you up emotionally (plus the story is top notch).

Martyrs (2008) is straight up painful, scary in it's own right and possibly the most disturbing "good" film I've ever seen.

Shutter (2004) will, again, give you nightmares.

Ju-On: The Grudge (2003) for well-known reasons.

Mandy (2018) is an A-class action-horror with Nicholas Cage fighting nether-hellish demons who killed his wife.

There are some really good short horror movies on youtube. One of my favorites is "Don't Move". It packs a lot into ten minutes, had to watch it a few times in a row to catch everything. Of cpurse, a lot are just hot woman gets jump scared but some are really good. "Post-apocalyptic Job Center" is funny but also really good.

Will always be The Excorcist. I stood in line for hours, got there early early morning, 1973.

Not a movie, but a BBC Christmas ghost story...BBC used to produce a ghost story at Christmas. The Brits like to blend creepy ghost stories in with their Christmas celebrations. Anyway, it's "Whistle and I'll Come to You." It is based on the M R James story of the same name. IMO, James was simply the best ghost story writer in the English language. The film is only about twenty minutes long. The actor Michael Hordern played the lead and he did a fantastic job. He really conveyed the deepest fear when he realized he was dealing with something not rational, a ghost in fact.

The final scene, in which the ghost has followed him back to his hotel room and manifests itself by raising up and forming the sheets on the extra bed into a body of sorts, just zinged me.

James made his ghosts malevolent and capable of harming/killing people, which is unusual for English-language ghost stories. Truly scarey shit, ghost stories for adults.

I left the light on the night I saw the exorcist

For me, now, I do not find any films to be scary at all anymore. Despite that I rarely watch any movies at all, I do try a 'scary' movie now and then to see if they're any good. Some do turn out to be decent, but only for their stories or plots; they're not scary at all, or even mildly suspenseful most of the time.

However, in the past I have seen a few movies that were scary to me.

Stephen King's IT I saw the original Stephen King's IT when I was a kid and it terrified me to the point of causing nightmares for a few nights. Seeing it the first time again years later as an adult still had some scariness to it, but not like when I was a kid. I can watch that now if I wanted to without it being scary at all.

I was a kid at the time, so noting that I had not read the book already before seeing the movie likely isn't needed, but still noting that I had not read it first.

Fear of the Dark (2003) In ~2003 I saw a lowish-budget movie called "Fear of the Dark" (the 2003 one). https://www.imdb.com/title/tt0308252/

I thought it was decent. Genuinely suspenseful scenes to me at that time. I wouldn't find it scary at all now, but it was good then.

Minor info about the film and an aspect of it that added to it being scary to me, not exactly spoilery: Plot info:

Why an aspect of it was particularly scary to me:

Phantoms (1998) Phantoms was based on the novel by Dean Koontz. I also had not read the book prior to seeing the movie. I found the movie to be genuinely creepy through much of it back when I first saw it in 1998.

At that time, Ben Affleck was not much more than a random actor I had seen in a few other things when I saw this. This was before his later film roles and life exploits.

Rose McGowan was also just some actress to me who had also played Titum, er, Tatum in Scream a couple years prior and this was before her later life exploits with Marilyn Manson.

Definitely not scary at all to me anymore.

The Thing (1982) Yeah, was scary as hell to me back when I first saw it in my teens. It's still suspenseful and creepy to me now, but not scary. Just a really good movie. Just like the scene(s) in Phantoms with the dog's back moving/rippling, the scene with the dogs in The Thing still makes me very uncomfortable.

Otherwise, I've seen some 'scary' movies that were alright, but the only real 'scares' in them were jump scares.

One film like that was "Apartment 143": https://www.imdb.com/title/tt1757742/

It had an obvious jump scare set up to happen and I knew it was coming, but the nature of the scene setup made me unsure which direction on the screen the scare would happen from and the nature of what I would see. As it still caused me to jump, I guess they did an alright job with it.

There are some movies that were scary and suspenseful at the time they came out when I watched them, but are complete jokes to me now.

e.g. The Ring Saw The Ring and later discovered that it was a remake of a Japanese horror film called Ringu. At that time it was also the start (or the catalyst) for all of the Japanese horror films being remade and 'Westernized' as shitty knockoffs and all of the tropes that came from that. Scary movies all started to revolve around having some pale-skinned Asian contortionist with oily black hair and crazy eyes climbing around on walls or doing supernatural things. This also fed back into that being what Japan and Korea started to produce because that was what Western studios produce and they think Western audiences like and want that in horror movies.

e.g. The Blair Witch Project Yes, The Blair Witch Project. Watched it alone and in the dark when it came out for rent. It was at a time when movies were still capable of being scary for me. Of course even thinking of that movie now makes me chuckle in my head a bit. That film also caused the whole "shakycam" craze that has destroyed movies and also completely stalled the development of any other kind of filming techniques.

If any specific movies are to blame for the destruction of the horror genre, it would be The Ring for causing themes of horror films to being limited to basically the same type of creature/character, and Blair Witch for causing the filming technique used in horror films to basically being shakycam.

I don't know that there will ever be a "best because everyone has different things that they think of as horror some are into the psychological, others gore, some phobias, etc.

Martyrs and Autopsy of Jane Doe haven't been mentioned yet, but both were solid films.

The original Hellraiser is my personal favorite, and I give it a watch every year. (Book was better, but that's typical.)

Ever since I went through a film-lit course back in '95, I do not find movies 'scary' any longer; rarely interesting. That said, I seen Nightmare on Elm Street when it came out (I was a child) and it mortified me - same Poltergeist. When I was older but not a teen, I watched the original Exorcist and was terrified but in a sense that I couldn't stop watching it. Love each of these movies today.

There must be a delineation between horror and gore - I am not entertained my gore, I find it tired and boring. Interestingly, and to that end, I am a huge Rob Zombie fan, so I will advocate for his stuff any day (you get some of both) - I really enjoyed his Halloween remakes - fucking violent, like in a 'release' kinda way.

The original Halloween is still my go-to, I play it every Halloween; Nightmare on Elm Street, Poltergeist, House of 1000 Corpses trilogy all get attention. One that I will advocate for that is an undiscovered gem is *Hereditary *produced by A26 studios.