Horror fans are a smart bunch and many are dubious the moment they start seeing phrases like "inspired by true events" or "based on a true story" thrown around during the opening credits of any film. There have been plenty of hoaxes and instances of truth-stretching in Hollywood over the years, both in horror and other "true story" films, including biopics and beyond.

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But with horror films, it is especially interesting because the possibility of one of these stories being 100% real would prove that ghosts and demons could be real too. Here are some of the most notable movies based on true stories, that aren't entirely true, and what they got wrong.

10. The Strangers

The strangers movie remake

When The Strangers was first released many hailed the film was extremely disturbing and one of the scariest movies of all time. It grew recognition for being so terrifying due to its realism. Especially because you find out in the end that the villains had no real motivation except the victimized family "was home." Even more frightening is that the movie was said to be inspired by true events.

Well, it was, sort of. The "true events" in question were actually just a childhood memory, or dream, that came from the mind of the film's director. He remembered a strange group of people knocking on homes to see if anyone was home, if no one was, they would break in. The opposite happens in the movie and none of this was necessarily true.

9. The Amityville Horror

There are two notable versions of The Amityville Horror and a myriad of other sequels that often went straight-to-DVD. The original film came out in the 1970s and starred Josh Brolin. Then a remake came out starring Ryan Reynolds in the 2000s. Neither version is entirely factual because the entire Amityville Haunting has long been suspected of being a hoax, or at least there are tons of conflicting testimonies that make portions of the haunting unrealistic.

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Even Ed and Lorraine Warren investigated this case at one point and the original Amityville home is still standing. Despite the controversy, it is still one of the most popular American hauntings of all time. Ronald DeFeo Jr. did shoot and kill his family, that much is true. And the Lutz family moved in years later, from there, everything becomes murky.

8. The Fourth Kind

As far as films based on true stories go, The Fourth Kind might be one of the biggest hoaxes of all. The movie claimed it was based on real stories of abduction after a group of people went missing in an Alaskan town. Part of that sentence is true. There was a strange period of time where many people went missing in Nome, Alaska, however, there was never anything to do with aliens.

The Fourth Kind even sets it up to appear like we're watching a fictionalized version of events alongside real documentary footage with an actual doctor. It's not true. Even the doctor was a hired actor and people from the set admitted the film was a hoax with the "true story" addendum a publicity stunt.

7. The Mothman Prophecies

the mothman prophecies

The Mothman is the stuff of legends in the way people like to believe in the Yeti or the Loch Ness Monster. He is part of an old urban legend that originated in Point Pleasant, West Virginia. Over the years, many witnesses have come forward claiming to have their own experiences with the fabled Mothman and it has never been proven.

John Keel wrote a book about the Mothman and other cryptids that was made into The Mothman Prophecies film. Some events in the film were said to have really happened which is why it claimed to be based on a true story, but there isn't hard evidence to back up the existence of an actual Mothman.

6. The Exorcist

The Exorcist's iconic house shot.

The Exorcist is one of the most iconic and famed horror films of all time. It is well-known that the movie was inspired by true events but the word "inspired" is used for a reason. The author of The Exorcist novel, which the film was adapted from, William Blatty, got the idea for his story by the real-life possession case of Ronald Hunkeler.

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He supposedly read about Hunkeler's case in the newspaper and it only shares a few similarities with the film. None of the pivotal scenes in the movie were based on truth, meaning the pea soup vomit was only a Hollywood creation. Blatty even admitted to faking most of it in an old Washington Post article.

5. The Possession

The spirit leaves the antiqu box in The Possession

This movie is a lesser-known film starring Walking Dead star, Jeffrey Dean Morgan. It tells the story of a family that comes into possession of a dybbuk box, which is a box thought to house a malicious spirit. In the movie, a little girl becomes possessed by the entity and the family has to do everything they possibly can to save her.

Dybbuk boxes are real things. Of course, there's no concrete proof that they contain anything truly evil but many are superstitious about them. However, the story of this film is completely fictional. But people who worked on the film claim strange things happened around the box, such as a mysterious fire starting after filming and burning all the props.

4. The Conjuring

The Conjuring is one of the most famous movies based on a true story. Demonologists Ed and Lorraine Warren were so well-known for their paranormal investigations, that they crop on this list numerous times because Hollywood loves adapting their case files into films. That was the case with The Conjuring. The film is based on the Perron family haunting in an 18th-century farmhouse in Rhode Island.

The house is still standing today, although it has been renovated frequently since then. Andrea Perron, the woman who wrote a book about what she experienced in the house, claims the film is mostly factual. But the one big difference is how much time it took. In real life, the actual haunting took place over a ten-year period, whereas in the film it is in a more condensed timeframe. Also, Perron never tried to murder her children as depicted in the movie.

3. The Exorcism of Emily Rose

The Exorcism of Emily Rose is praised as being one of the better "true story" horror films out there but even this movie doesn't get everything right. For starters, the case this was based on wasn't about a girl named Emily Rose. The real girl's name was Anneliese Michel. The bulk of the movie focuses on the court case that came after Emily's death.

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Who was responsible for her death? The film is about the legal part of the case but in real life, the religious aspects and exorcisms were a far bigger part of the conspiracy. The medical issues in the film are not 100% accurate either. Emily's last-known seizure occurred four years prior to her death, she wasn't having them up until her final moments as depicted in the movie.

2. The Haunting in Connecticut

Three people hold hands around the table in The Haunting in Connecticut

The events of Haunting in Connecticut were said to be based on a book called In a Dark Place: The Story of a True Haunting, an account of the Snedeker family and the horrors they faced in their family home. Ed and Lorraine Warren investigated this case and Lorraine believed the home was owned by former morticians who practiced necromancy.

The author of the book, Ray Garton, has publically distanced himself from the film and claims of the book's accuracy. He, and other authors, who have worked with the Warrens, claimed they were paid to make up stories and add details to heighten the scare factor.

1. The Texas Chainsaw Massacre

As one of the most beloved slasher franchises of all time, The Texas Chainsaw Massacre also serves as one of the most gruesome. Knowing how gory the film is, it might surprise you to learn it was based on a true story. Leatherface was inspired by the real-life serial killer, Ed Gein.

However, the term "based on a true story" is only applicable in the shallowest sense of the term. While Ed Gein did indeed wear a mask made of human skin, it wasn't because of any facial deformity. Gein had a desire to be a woman. He also used a pistol to kill his victims and not a chainsaw.

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