For horror movie fans, the genre has taken several directions with its subgenres, but even die-hard fans find that upsetting horror films are difficult to watch. Horror is meant to evoke reactions like fear, disgust, and sometimes humor, and most scary films do that well enough.

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However, a particular handful of horror flicks have caused more discomfort than fear in viewers. These films upset the viewer and leave them thinking about the movie long after the credits roll. From overly vivid murders to upsetting concepts that could be true, some horror films feature sad and dark themes.

10 Hostel Is A Chilling Tale Of Trafficking

Paxton bound and trapped in the prison

Traveling is meant to be a fun and exciting experience for people in the real world, but the film Hostel takes it to dark extremes. In Eli Roth's horror film, young tourists are kidnapped and become victims of trafficking. While the first movie is disturbing enough, the story carries on for another two films.

In Hostel, the tourists are encouraged to visit a hostel in Slovakia where they are promised female company. They are then taken to a secret location, and wealthy individuals pay a fee to torture and kill the unsuspecting victims in the most gruesome manner. After that, Hostel details every brutal moment of torture, making for an upsetting watch.

9 A Clockwork Orange Is A Controversial Classic

Alex and his droogs in the club in A Clockwork Orange.

A 1971 adaptation of the dystopian novel of the same name, A Clockwork Orange explores themes of morality and what it means to be "good." While the Stanley Kubrick film has been labeled a cinematic masterpiece by most for its technical aspects, the plot has incredibly dark images and has been a source of controversy for its "morally offensive" visuals and "extreme" violence.

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A Clockwork Orange doesn't appear like a typical horror flick, but some would place it in the genre for its distressing scenes. The callous behavior of the Malcolm McDowell's Alex and his fellow gang members make the audience increasingly uncomfortable. The characters' violent actions distressed and upset viewers.

8 The Last House On The Left Depicts Graphic Violence Against Women

The father threatening the criminals with a chainsaw in The Last House on the Left

Wes Craven, best-known for his iconic work on horror films like A Nightmare on Elm Street and Scream, made his directorial debut with The Last House on the Left. The horror film details the story of Mari and her friend Phyllis, who are out celebrating a birthday when they run into a violent group of escaped convicts.

The group of criminals kidnap and sexually abuse Mari and Phyllis. Mari attempts to escape when her friend is killed, but she doesn't get out. The Last House on the Left's only saving grace is when the criminals unknowingly stumble into Mari's parents' home while looking for shelter, and her parents get revenge. Craven's horror flick was censored in Australia, the United Kingdom, and the United States, as many audience members were so upset that they destroyed the film.

7 House Of 1000 Corpses Utilizes Shock Factor To Leave An Impact

Captain Spaulding talking to his customers at the gas station.

The 2003 Rob Zombie film, House of 1000 Corpses, pits a group of friends against a family of killers in a rural location. While the morbid comedy has become a cult classic since its release, Zombie's inclusion of explicit violence would make most audience members uncomfortable.

While murderers are never liked in horror films, some fans might think of the Firefly family as antiheroes or sympathetic villains because Zombie paints them as charismatic people. Realistically, though, that makes them even more terrifying. Despite the tidbits of humor, the darker images of mutilation and torture in House of 1000 Corpses might be hard for some to stomach.

6 The Strangers Is A Realistic Fear Of Home Invasion

The trio of strangers invading the couple's home in The Strangers

Filmmakers of The Strangers drew inspiration from the Manson Family murders for their 2008 psychological horror flick. Still, some have noted the similarities between the movie and other real-life cases, making the film all the more disturbing.

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The Strangers focuses on a couple who are staying in a secluded home when a trio of strangers breaks in and enter the house. The strangers lock the couple inside and taunt them. Instead of robbing the couple for their belongings or money, the criminals torture and eventually murder them. Before the couple are killed, they ask why this is happening. One of the offenders simply states: "Because you're home." The Strangers is upsetting and terrifying because it could happen in real life.

5 The Exorcist Is Horrifying To This Day

Regan talking to one of the priests from her bed

Nothing could prepare 1973 audiences who had to witness a little girl and her mother fight off demons in some of the most visually terrifying and disturbing scenes in horror. The Exorcist depicts twelve-year-old Regan MacNeil being possessed by a demon throughout the film.

As popular as exorcism and spiritual horror films are, no movie has left quite the impact as The Exorcist did. At the time of its release, the haunting images of self-mutilation, archaic medical practices, and the physical deterioration of Regan made viewers so upset that they fled the theater.

4 Mother! Is A Warning Of Destructive Human Nature

Mother and Him getting lost in the crowd in their home

The 2017 psychological horror film Mother! stars Jennifer Lawrence and Javier Bardem as a happy couple whose lives are disrupted when their house becomes overrun with unwelcome guests. The simplistic storytelling of the film doesn't outweigh its unforgettably powerful and upsetting visuals.

Some fans have noted the similarities between Mother! and biblical stories, while others have seen the movie as a metaphor for humans disrespecting and violating the earth. After the titular mother has given birth, horrific visuals of infanticide take place, which upsets even the most composed viewers.

3 Midsommar Is A Brightly Lit Cult Film

Dani screams in Midsommar

Ari Aster has made a name for himself in the horror genre with his upcoming release of Disappointment Blvd. and his disturbing debut, Hereditary. Still, his 2019 film Midsommar shocked audiences to their core. The horror movie features Florence Pugh as Dani, a woman who attends a midsummer festival in Sweden with her friends after the murder-suicide of her parents and sister.

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Although the protagonists initially considered the commune to be welcoming and overly friendly, they end up having trouble stomaching the commune's brutal practices. By the end of Midsommar, Dani is manipulated by the midsummer celebrators, eventually encouraging the brutal murder of her boyfriend. The film becomes increasingly difficult to watch.

2 The Purge Shows A Dystopian Potential Of Corrupt Politics

A masked purger looking at their next victim outside

The film that spurred a franchise of sequels and prequels, The Purge is a culturally significant movie despite its dark and gruesome images. It plays out mostly the same in each installment, but every film carries a lot of weight. In The Purge, The United States has become a crime-free dystopian society where all illegal activity is decriminalized for a 12-hour slot on the annual "Purge" holiday.

In each Purge film, the protagonists do their best to stay out of harm's way and lock themselves indoors for safety. The Purge is a disturbing social commentary about corrupt politics and humanity's affinity for violence, which makes the film even more distressing.

1 Terrifier Has One Of The Most Offensive Kills In Horror

Art the clown smiling at the girls in the pizzeria

Terrifier is a slasher film about a clown named Art and his Halloween killing spree. The clown chooses to stalk two friends at a restaurant where he butchers the workers and kidnaps one of the women, later hunting down the other.

Though Terrifier is a typical slasher film, with Art killing anyone and everyone in his way, one of the most infamous scenes involves a brutal medieval-like murder, which is done with a saw to one of the girls. The murder is filmed so unabashedly that it has become the most hard-to-watch and upsetting horror scene.

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