The line between psychological horror and psychological thriller is razor-thin, as seen in Orphan: First Kill. The rules that apply to one typically apply to the other, because both subgenres are simultaneously seeking to frighten the audience and make them think.
Over the years, psychological horror films such as Get Out have come along that point a finger at these tropes and dig deeper. Then there are those of the psychologically scary movie subgenre that flip the script altogether.
10 Nothing Is Scarier — Saw (2003)
Defined by thrillers such as Steven Spielberg's Saw isn't the bloodiest film in the world, but it was a fairly clear ringing of the bell that sequels would up the gore factor substantially.
Even in the original film, however, the production design was fairly loud and quick. There may be some movie characters that can survive Jigsaw's traps, but the viewer could be fooled from thinking so via the series' rapid-fire editing and thundering score. By the time Saw: The Final Chapter rolled around, there were still the constant cuts, but merely to more images of gore, not away from it.
9 Creepy Animals — I Am Legend (2007)
the saddest animal deaths in film history, but up until that traumatic moment Sam the dog is Dr. Robert Neville's greatest ally. Sam's a sweetheart, a hero, and the polar opposite of the creepy crawlies usually seen in the psychological horror genre.
And I Am Legend (like The Omega Man with Charlton Heston before it) certainly has its horrific elements. That said, there are no undead vampire people roaming the Earth that can upstage the trauma of watching Sam away, either for Neville or the audience.
8 Buried Alive — Dolan's Cadillac (2009)
Stephen King's "Dolan's Cadillac" was a novella published in monthly chunks via the author's newsletter. It eventually found itself included in "Nightmares & Dreamscapes" (the book, not the 2006 miniseries) before ultimately receiving a cinematic adaptation three years later.
Unfortunately, it was a direct-to-video release, making it one of the lesser-known King adaptations to date. But it has a solid central concept: a grieving man exacts revenge on the crime boss who killed his wife via live burial in his precious Cadillac. It's a slow-burn process that ups tension, and thanks to Christian Slater's per-usual solid work as crime boss Dolan, the film's a worthy DTV film.
7 Non-Chronological Timeline — The Wicker Man (1973)
Featuring one of The Wicker Man is fairly straightforward. The movie opens with Police Sergeant Neil Howie flying to an island to begin his missing person's investigation. It ends with his demise.
Unlike psychological horror films such as Identity, The Wicker Man is utterly chronological. It's just that the information being provided Police Sergeant Howie is a massive fabrication, at best. By the time he realizes this, it's too late, and he's within the burning "Wicker Man."
6 No Concrete Ending — The Cabin In The Woods (2012)
still manages to be an easy-to-watch horror movie, as well as re-watchable. It plays with just about every formula in the book, regardless of horror subgenre. Any movie that has a unicorn charging a machine gun-toting soldier to the point of impalement is a movie that's swinging for the fences, and The Cabin In The Woods hits its mark consistently.
The third act is especially surprising, but perhaps never more so than the final shot, where an unappeased God's hand bursts from the center of the Earth and begins its quick slapping descent. It's utterly conclusive, even if the camera cuts to the credits before it happens.
5 A Totalitarian Authority — Equilibrium (2002)
Actor Christian Bale missed out on The Matrix, but he managed to get the next best thing in Equilibrium. Like the Wachowskis' film, it's a violent, dystopian science fiction adventure with a stoic lead performance. Like Keanu Reeves' Neo, Bale's John Preston can outmaneuver just about anyone in a gunfight, but the point of comparison more or less ends there.
Neither The Matrix nor Equilibrium fit the traditional mold of a horror film, but they certainly have their moments (e.g. Neo's birthing scene in The Matrix) and both are deeply cerebral. But, in the former film, it's a man on the run. In the latter, it's the man doing the chasing who receives the focus, soon learning that he's not doing what he's supposed to.
4 Drowning — Titanic (1997)
Redditors may think James Cameron's the most pretentious movies they've seen, but it's widely considered a modern classic nonetheless. It's also an inversion of a typical psychological horror character trait: The fear of drowning. In Titanic, one character spends a lot of time in the water but never gets a chance to develop the phobia.
The scene with Jack bobbing in the ice-cold water as Rose (also shivering) is lying on a big piece of carved wood has been discussed and memed to death, specifically, that Jack's death was unavoidable. Overall, Titanic shares far more tropes with the disaster film than a psychological horror piece, but the long, slow freezing is a memorable adjustment of the drowning trope.
3 Unexplained Symbolism — Man Of Steel (2013)
The Man of Steel just grew exponentially. This is great news for the original film's die-hard fans, though it does remain to be seen who will be sitting in the director's chair. Detractors of Zack Snyder's DCEU debut installment cite many concerns, with one of them being its tendency to be thematically on the nose.
It's the inverse of a psychological horror film (even if Man of Steel does have its frightening stakes), where the message is typically kept secret until the third act so as not to spoil any surprises. But in Snyder's film, the word "Hope" is paraded often and, depending on who is asked, put to fairly good use.
2 Seeing Ghosts Or Demons — The Others (2001)
No being torments quite like a ghost, which is why so many psychological horror films such as The Others incorporate them. However, it's a deviation from the formula that's not readily apparent from the start. The film follows Nicole Kidman's Grace, a devoutly religious single mother who moves her two kids away from danger during World War II.
Grace has strikes against her at the moment, e.g. a missing husband and two kids with bizarre, extreme photosensitivity. There are also a couple housekeepers who seem to have an ulterior motive. Really, they're just more informed of their status: like Grace and her kids, they're the ghosts.
1 Someone's In Pursuit — First Blood (1982)
For John Rambo, the first half of First Blood is absolutely a psychological horror film. For Chief Deputy Art Galt and his men, the second half of First Blood is just the same. The psychological horror film is about torment, and that typically involves stalking e.g. It Follows.
First Blood is that concept times two, and the narrative is all the better for it. The original Rambo movie is an action film on the surface and a thinker beneath. It also shows two distinct factions: one is a law enforcer, who's meant to be out for the good of the people, out for someone who fought for the country. The other is the war-hardened vet who just wanted to see a friend. By the end of the movie, it's clear that the latter "stalker" (or hunter) actually has a survivalist motive to do so.
