horror movies people thought were real
[Photos via Open Water/Lionsgate, The Blair Witch Project/Artisan Entertainment, The Strangers/Rogue, Paranormal Activity/Paramount]

Fall is officially upon us, and that means it’s time to prepare for the spookiest holiday of the year. With Halloween comes an uptick in horror movie releases and consumption. With so many films on the market, studios have to think outside the box for ways to keep audiences scared. One way to do this is to give a fresh take on a genre classic, such as Insidious. Another is to convince audiences that the film they’re watching is something that really happened.

These movies use a combination of methods to fool audiences—often it’s the “based on a true story” or “true events” type of disclaimer at the beginning of the work. Or, it’s the use of found footage, which was so groundbreaking when it first dropped that audiences were blown away. Here are 10 films that were so scary that people thought they were real.

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Paranormal Activity

This 2009 found-footage film was widely thought to be real when it first debuted. Paranormal Activity, which was filmed entirely on a home video camera, tells the story of a couple, Micah and Katie, who believe their home is haunted after strange things begin to happen. Micah brings in a video camera, which captures a lot of the paranormal activity named in the title. The film is considered the first “viral” movie, as it got a small release initially. However, the film caused 1 million people to demand the film be shown in their town in less than a week. This was largely due to word of mouth (and obsession over whether the film was real or not). 

The Blair Witch Project

The 1999 film that revived the found-footage craze, The Blair Witch Project follows three film students as they hike into the woods searching for the fabled Blair Witch. After a chain of spooky events and lots of fighting between the trio, the aspiring filmmakers end up in a spooky house with their fates unknown. The film’s success with tricking audiences to think it was real came down to marketing and production. The flick’s website was marketed as an investigative website seeking to find the hikers—Heather, Mike and Josh. Additionally, they intentionally left out any music in the film and made sure the lighting was as natural as possible. 

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Quarantine

Based on the 2007 Spanish film Rec, Quarantine follows a group of people as they’re quarantined in a Los Angeles apartment complex after an alleged outbreak of rabies. It’s another found-footage vehicle that made viewers cringe as the infected chase after the uninfected in close quarters. Additionally, the use of the shaky camera movements also made the film feel like a real occurrence and probably gave a viewer or two a bit of nausea. 

The Strangers

The film opens with the ubiquitous “inspired by true events” line. However, it took this theme up a notch and added a recounting as though it was an actual case. The opening lines end with “the brutal events that took place there are still not entirely known,” thus priming audiences for a film that seemed to emulate a real-life murder. The Strangers achieved its goal of scaring audiences and making them feel unsettled enough to search for whether the film was based on a true story. The reality is that director Bryan Bertino based parts of the film on the Tate-LaBianca murders committed by the Manson family

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Cannibal Holocaust

Often dubbed the most controversial film ever made, Cannibal Holocaust is a 1980 found-footage film that follows a group of American filmmakers as they search for their colleagues who went missing in the Amazon. The film features a deluge of disturbing content, everything from torture to animal mutilation to graphic depictions of cannibalism. Being the first film of its kind, many thought the events actually happened. According to director Ruggero Deodato, the people of this region actually practiced cannibalistic habits. However, that didn’t stop audiences from calling Deodato racist and taking issue with the disturbing nature of the film. 

Snuff

The 1976 film, also based on the Tate-LaBianca murders, follows a pregnant actress and her producer as they take a trip to South America. There they meet a biker gang lead by a man named Satan, who terrorizes the actress and her friends. The film has several scenes depicting violent murders, including a graphic disembowelment. According to Coming Soon, the film was protested, and police departments allegedly investigated whether or not Snuff was real. 

Quiz: Can you figure out these horror movies by their plots? 

Faces Of Death

This 1978 film features vignettes of humans and animals being killed. Each section is narrated by a pathologist who claims to be interested in life and death and thus decided to study the “faces of death.” This film is the first in a series, and though most of the footage is fake, there are some scenes that are real. Faces Of Death is allegedly so controversial, it even boasts a tagline that says “Banned in 46 countries.” 

Ghostwatch

In 1992, the BBC aired a film called Ghostwatch. In it, a family is terrorized by a malevolent presence in their home. The film follows the alleged investigation into the haunting, complete with a creepy moment of a young girl showing the “investigators” where the ghost “lives.” Because it was marketed as a real paranormal investigation that took place “live,” children across the country were scarred by what they saw. According to NewStatesman, the show was so disturbing that some children were traumatized by it, with one ending up in an inpatient unit.

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Guinea Pig 2: Flower Of Flesh And Blood

This 1985 Japanese horror film caused controversy in both Japan and the United States. The film follows a man who stalks and kidnaps a woman to dismember her for his “collection” of body parts. The movie, which is based on director Hideshi Hino’s manga, was pulled from video distribution for its graphic killing depiction. Additionally, the violence in the film seemed so real that Charlie Sheen sent a copy to the FBI for it to be investigated. However, the investigation was quickly dropped after it was revealed that the graphic scenes were done using special effects. 

Open Water

Perhaps one of the scariest films set at sea, Open Water is about two divers who get separated from and eventually left behind by their crew. The pair is stuck miles out into the ocean and are faced with dehydration, exhaustion and shark attacks. The film isn’t real, but it was loosely based on Tom and Eileen Lonergan, who disappeared in a similar fashion. However, the true events around what really happened to the Lonergans aren’t known. As a result, the filmmakers behind Open Water took some liberties with explaining what may have happened to the couple. 

Which movie on this list scared you the most? Let us know in the comments.