The horror genre is full of scary things. From ghosts to demons, and serial killers to aliens, there are many things that could easily hurt us. But, what happens when we're alone? Sometimes the most terrifying thing then is our response to self-imposed or forced states of isolation and loneliness.

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One of the most dangerous things in the world can be the human mind. Thoughts can play tricks that lead to danger. In these ten horror movies, characters find themselves by themselves, or close to it, for various reasons. As time goes by, they realize that perhaps they weren't so alone after all. That maybe, just maybe, something was always there, waiting for them.

Without Name (2016)

In an ancient Irish forest, a land surveyor spends his days working by himself, and his nights fearing what may be out there in those dark woods. And, it doesn't take long before his mind starts to go. Are these woods not so uninhabited after all?

Without Name is a little-known Irish horror movie and slow burn. It's also full of beautiful, lush cinematography thanks to the film's natural and untouched environment. It's a creepy movie that shows what happens when we enter nature's realm without her permission.

Man Vs (2015)

Doug Woods is a survivalist television show host who is looking to film a new episode. He's dropped off in the Canadian woods where he will film said episode all by himself. Now, all seems well until Doug notices things are amiss at his solitary campsite. Someone — or something — is hunting him.

Man Vs sounds like a horror version of Man Vs Wild. That's precisely what it is. Chris Diamantopoulos (The Office) carries this movie on his own, and what eventually happens in the movie has to be seen to be believe. The ending is one you won't forget.

It Waits (2005)

A troubled forest ranger self-isolates in the woods after experiencing a personal tragedy that forever changes her. She's miserable and all by her lonesome, with the exception of her pet bird and a handsome visitor. Her sad state of mind takes a reprieve, however, when there appears to be a dangerous and very large creature lurking nearby.

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Cerina Vincent (Power Rangers: Lost Galaxy) goes toe to toe with a horrifying, otherworldly interloper as she seeks atonement for her past.

Of Unknown Origin (1983)

Bart Hughes is a pretty average father and provider. Yet, when his wife and son go on vacation without him, Bart finds himself becoming more and more obsessed with a home invader. Not another person, but something of unknown origin.

Malefic beasts and perilous pests have frequented horror and sci-fi for decades. While they might seem easy enough to deal with in real life, the creatures in this 1983 movie prove to be nothing short of cunning.

Dominique is Dead (1978)

A greedy American named David Ballard lives in England with his wife, Dominique. His reprehensible behavior then drives his wife to suicide. David thinks all is good now that she's gone, but he's suddenly haunted by his late spouse's spirit, who roams their spacious estate at night.

The tables are wonderfully turned in this low-key British horror. Back overseas, it was simply called Dominique, whereas in the United States, it was renamed Dominique is Dead on home video. Either way, this is a movie that asks us if we really believe David is being visited by his wife's specter, or if this is something else altogether.

Hostile (2017)

In a post-apocalyptic future where a pandemic has ravaged most parts of the world, one woman ends up wounded and alone in the desert. Well, not entirely alone as there are hordes of horrible, malevolent creatures outside her overturned vehicle, waiting to get to her.

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Hostile is an interesting indie horror as it chronicles both the current situation as well as the protagonist's history, and what led to this moment in time. It's a sobering and often sad horror drama with some commendable creature effects and makeup.

I Am the Pretty Thing That Lives in the House (2016)

i am the pretty thing that lives in the house poster

A retired horror writer with dementia is taken care of by a live-in nurse named Lily Saylor. The longer Lily stays in her client's house, the more she believes a presence is haunting them.

Horror fans are divided about Osgood Perkins' (Gretel & HanselI Am the Pretty Thing That Lives in the House. As far as atmosphere goes, this haunter has it in spades. It's an unnerving and uncomfortable film where not a lot happens, but that fact only adds to the eldritch terror at hand. Those less pleased with the movie find the pacing to be tedious.

Ritual (2012)

A man named John wakes up buried in the forest and with no memory of how he got there. His cellphone has no contacts, and he thinks someone may have tried to kill him. As he investigates how he ended up in that grave, John finds the truth is far more shocking than he could have ever expected.

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Joko Anwar's Ritual (or Modus Anomali) is an English-language Indonesian thriller full of twists and turns. To boot, it's a bloody mystery that reminds us of the director's passion for evocative violence and frenzy.

Mischief Night (2013)

A teenager named Emily suffers from psychosomatic blindness. The condition stems from the car accident that took her mother's life. Now, she lives with her father. One evening, which so happens to be Mischief Night, or the day before Halloween, Emily is left home alone as her father goes on a date. Little does she know, a masked killer in a yellow raincoat has broken into her house.

An intriguing plot lures slasher and home invasion fans to this underseen but rewarding hidden gem.

Creep (2004)

Party hardy Kate gets trapped in the London Underground one night after a long bout of fun. The more she tries to find a way out, the deeper she embeds herself in a part of London no one knows about. To make matters worse, there's something sinister stalking her.

Franka Potente of Run Lola Run fame plays a character cursed with bad luck. She enters the Tube thinking she's on her way home when she's really entering what is practically the mouth of Hell. For something unspeakably horrid is down there with her and anyone else who was unfortunate enough to get caught after hours.

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