With spooky season in full swing, people may be browsing different horror movies looking for a good scare. An innovative and experimental marketing technique that began being used by horror movie production companies in the '90s was suggesting that the events unfolding on the screen were more documentary than fictional in order to really get under audiences' skin.

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To this day, some movies released in the horror genre not based on any well-known true event have fans on Reddit convinced that the plot is real - whether it's because of clever marketing or a rumor about a curse upon watching.

The Blair Witch Project (1999)

The Blair Witch Project missing poster and screen grab

The Blair Witch Project, about a group of filmmakers trying to find the Blair Witch in a forest, is one of the most well-known horror movies to use their marketing to imply that the story was real. A user on Reddit details their strategies, sharing that the actors even used their real names in the film instead of character names, and there were missing posters put up for the cast and crew.

An added level of realism was provided by the fact that all of the lines were improvised - a behind-the-scenes fact about The Blair Witch Project. This, along with the promotion, made moviegoers sure that the people featured in the film had actually gone missing in the forest. Many users chimed in that they, too, thought that it was real until they saw actors do interviews about the project.

Paranormal Activity (2007)

Katie walks in a trance in Paranormal activity

One of the best horror movies about a haunted house is none other than Paranormal Activity. The film has been referenced in many other movies and TV shows, proving the effect it had on media. Falconbox on Reddit even shares the top Google query at the time of release was  "Micah Sloat obituary" and other questions about Katie, the other protagonist, revealing that viewers thought that the story being told by Paranormal Activity was true.

People were so terrified of the film that they many actually walked out of the theater in fear, leading those on the production side to initially think that the movie was poorly received. They later found out that the horror movie was just working too well.

Antrum (2018)

A title card for the movie Antrum, two children sit on a rock

Antrum hit audiences with some real-story-inception: the film was supposedly a documentary about a "cursed" movie. The beginning is about the making of the documentary and the events that unfold, and the second part is the supposedly cursed movie tacked on to watch.

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Antrum was marketed as "the deadliest film ever made," with rumors circulating that watching it caused disasters and death and even included a legal warning at the beginning of the movie with a countdown to its start time. One Redditor, UndeadManoto17, shared that they heard a chant in Antrum allows demons to enter viewers' homes.

The Exorcist (1973)

Linda Blair As Regan in The Exorcist

Another film that reportedly had an effect on the people who watched it was the timeless '70s horror film The Exorcist. For its time, The Exorcist was groundbreaking and terrifying. Exorcism movies were not all that common in the '70s, and the disturbing imagery was enough to frighten the living daylights out of moviegoers.

Redditor Penitentialarts mentions that people talking about feeling sick or having panic attacks after watching the film fueled widespread pandemonium, and theories have abounded about what the movie is based on, with some saying a real exorcism performed on a boy possessed by an ouija board inspired the film.

Cannibal Holocaust (1980)

Two characters talk in the woods in Cannibal Holocaust

Viewers thinking this particular horror movie was real actually had legal repercussions for the director, Ruggero Deodato, according to Reddit user Yourownbiggestfan. They share that Deodato was accused of murder because of rumors that the film depicted real deaths instead of manufactured gore.

The charges were dropped, however, when the supposed victims were able to testify that they were, in fact, alive. This isn't the only rumor that has followed the 1980 horror flick; viewers also theorized that the sex scenes of the film were actually real as well, instead of simulated. For gore fans who draw the line at animals, Cannibal Holocaust also features several instances of animal cruelty, although there is an option on the DVD version to watch it without.

Ghost Watch (1992)

Hosts discuss haunted house on Ghostwatch

Across the pond, British audiences were getting equally spooked. IrishinManhattan617 and other Redditors discuss the made-for-TV horror feature on BBC that had viewers convinced that an entire news crew had been terrorized. People watching the Halloween special figured that the news team was doing the feature for the holiday, and "hosts" of the program were two well-known and trusted faces of British media.

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Many people were completely duped by Ghost Watch, and actually thought that they had just witnessed a news team be murdered by supernatural forces in the "most haunted house in Britain." Although it didn't have any elaborate marketing, the fact that it didn't outrightly state that it was fake was said to have inspired other movies like The Blair Witch Project. 

The Fourth Kind (2009)

A man screams in bed in found footage from The Fourth Kind

The Fourth Kind depicts an investigation into the disappearance of several people in Alaska and links strange video interviews with alien abductions. Users like Stettler admit to Reddit that they were convinced the events were real, and the discussion was an extensive one. Another user, VinceVenom shared that their friend debated for half an hour that the found footage in the movie was genuine.

There is a bit of truth to it, though, as some say the inspiration for the film was a string of missing person cases in Alaska that were previously unsolved, but FBI investigations sadly revealed with the discovery of some of the victims that freezing temperatures and alcohol was the most likely culprit responsible for their passing. Some say the marketing for The Fourth Kind went too far by profiting off of these sad deaths.

Incident At Loch Ness (2004)

two men look out at the Loch in Incident at Loch Ness

What made this film trick audiences before its release, was the fact that famous documentarian Werner Herzog, was a part of the film and everyone plays themselves, not unlike The Blair Witch Project. To make things even more ambiguous, news articles started circulating after Herzog was spotted in Scotland, detailing that he was beginning filming on a documentary about the Loch Ness monster.

Reddit user Bvaugh adds that Herzog uses all of his trademark documentary techniques to give the movie the same feel as his actual documentaries. This, added with the fact that the Loch Ness Monster is a real-world urban legend, made fans question if the story was based in fact.

Guinea Pig 2: Flower Of Flesh And Blood (1985)

Charlie Sheen Over a Still of Guinea Pig 2

This is another horror movie that did its job perhaps too well and prompted a call to the authorities. HanaaaLucie posted to Reddit about Guinea Pig 2's supposed claim to fame: upon watching the film in 1991, actor Charlie Sheen was so certain that he had just watched a snuff film, that he called the FBI to do an investigation into the film's production.

Although the investigation was quickly closed due to the fact that Guinea Pig 2 included actors and movie gore, it speaks to the quality of special effects that the film utilized for its time. Some horror movies don't need gore to scare audiences, but fans of fake bloodshed even still find Guinea Pig 2's gore to be especially unsettling.

Man Bites Dog (1992)

Ben aims a gun in Man Bites Dog

Released around the same time as Cannibal HolocaustMan Bites Dog is credited with the true beginning of mockumentary-style horror. The film depicts a crew following around a French serial killer throughout his day-to-day life. The beginning of the film is darkly humorous, with a quick turn into the disturbing that makes viewers feel sick for laughing along with such a seemingly charismatic villain.

Redditors like Al_Scarface_Capone outline the tactics that Man Bites Dog employed, long before the days of Blair Witch and it's a best-ranked film on Rotten Tomatoes by one-time directors Belvaux, Bonzel, and Poelvoorde. Part of what really shook audiences was the main character's captivating and realistic performance, making them question the film's veracity. Viewers should be warned that this movie does contain sexual violence, so they should watch it at their own risk.

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