Content Warning: This movie discusses violent, real-life crimes.

The phrase "Based on a True Story" is used very frequently when it comes to horror movies. The phrase is usually seen as nothing more than a way to get people in the seats, but oftentimes, it's a warning that the events in the film are, at least in part, based on something terrible that actually happened.

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Watching a scary movie is nerve-racking enough, but the knowledge that the story unfolding really happened adds a whole other level of fright. Horror fans have the streaming service Shudder tailor-made for them to enjoy horror films of all kinds, and there are plenty of true story horror films to add a little extra fright to their day.

The Texas Chainsaw Massacre

Sally and her friends meet the Hitchhiker in Texas Chainsaw Massacre

One of the films that helped create the slasher genre was 1974's The Texas Chainsaw Massacre. This iconic fright film was terrifying to audiences when it originally released and still is to this day.  While the film itself is a complete work of fiction, some of the more grotesque elements are based on Ed Gein, the same man who inspired characters such as Norman Bates and Buffalo Bill from The Silence of the Lambs.

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Those who are familiar with Gein know that he was one of the worst examples of a real-life monster. While the original film never claimed to be a real tale upon original release, as Gein was still alive and in captivity, the 2003 remake did claim it was a true story.

Angst

K lurking around outside a building in Angst.

Released in 1983, Angst is a little-known cult film from Australia about a psychopath let loose into the world. The plot may not sound like anything too unique, but Angst is one of the most controversial films of its time. The content within the film is deeply disturbing and was banned for some time in several countries.

What makes the film even more horrifying, though, is that the main character is based heavily on mass murderer Werner Knesek. Werner held a family captive while on parole, which is the plot of the film. The movie is not for the faint of heart, and even to this day, it remains one of the more disturbing films on Shudder.

Lizzie

Chloe Sevigny as Lizzie Borden in Lizzie.

The tale of Lizzie Borden is so well known, there is even a rhyme about it. There have been countless films made revolving around the murders from 1892, with one being made in 2018 starring Kristen Stewart and Chloe Sevigny in the title role. This movie takes heavy liberties with the legend, most notably Lizzie's lesbian relationship with Bridget Sullivan, which is mere speculation but was shown to be a fact in the film.

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Regardless, a majority of things in the movie reportedly took place, including the grizzly end Lizzie's parents were met with. While not the most historically accurate, the film is the only adaptation of the story currently on Shudder, and it is chilling to know it mostly happened.

Black Christmas

Jess on the phone with Billy in Black Christmas.

While the slasher classic Black Christmas may be fiction, the film's most chilling scene is inspired by a very real urban legend. The story goes, a young girl is home alone when she receives a call. While on the phone with the stranger, she becomes more and more terrified as she phones the police. The police inform her that the calls she has been receiving are coming from within her own home, meaning the culprit is there with her.

It has been debated for decades whether or not this story is real, but that doesn't make it any less terrifying. This premise planted the seed that would become Black Christmas, and in the process, helped launch the slasher genre.

Amityville 1992: It's About Time

Characters discuss the haunted clock in Amityville 1992.

One of the most infamous true-crime stories is the tragedy that took place in a house in Amityville. The first film based on the events, The Amityville Horror, is one of the most well-regarded horror films from the 1970s. Despite it being heavily influenced by true events, there were several sequels. It seemed as if each entry strayed further from the original story, and the sixth entry is no exception.

After the fictional version of the house was destroyed, the series focused on cursed objects from the house, with a clock being the focus of Amityville 1992: It's About Time. While being lackluster in comparison to the original, this film has been regarded as one of the better sequels, and Shudder has it for all to enjoy.

True Horror

Bill sitting among the carnage in True Horror.

While being the home for classic fright flicks, Shudder also houses its own original content. One of the best received is an anthology series from 2018 titles True Horror. The four-part series is based on real-life testimonies from those who have encountered the unthinkable.

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Each episode fills the viewer with dread and torment, and the knowledge that it is all supposedly real is what makes it even worse. Those who have even the slightest belief in ghosts or the paranormal will find this series one of the scariest things on the entire site.

La Llorona

Maria Mercedes Coroy as Alma in the water surrounded by lilypads in La Lllorona

The legend of La Llorona has been adapted several times for the screen. Most notably, The Curse Of La Lloronawhich has a loose connection to The Conjuring films. Shudder has one that is unfortunately overshadowed, however. Simply titled La Llorona, the film brings the legend to life in a way even the Conjuring film failed at.

The movie is a horror film masquerading as a political drama. A good chunk of the film involves a man standing trial for the crimes of his past, while the horror elements creep in when the viewer least expects it. The film puts a clever twist on not only the La Llorona legend, but also on horror in general, and it is a worthy addition to Sudder's original lineup.

Cursed Films

Linda Blair discussing the making of The Exorcist in Cursed Films

While a docu-series, the Shudder original series Cursed Films can be just as unnerving as the films they discuss. Any horror fan knows that the industry is full of curses and unexplainable events. This mini-series looks at one supposedly cursed film per episode and the true accounts of those who worked on them. While horror hounds are familiar with some of these stories, there are many that may have slipped past their knowledge.

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From the possession of the crew on The Exorcist to the tragedy during the filming of Twilight Zone: The Movie, there are plenty of bizarre events plaguing the production of these films. Oftentimes fans can just repeat to themselves, "It's just a movie," but if the movie itself is haunted, all bets are off.

The Hills Have Eyes

Bobby peers over a rock in The Hills Have Eyes

Years before he changed the face of horror with A Nightmare On Elm Street, Wes Craven made a gritty film about a family that encounters a group of savages when their car breaks down in the desert. The story of the film is a work of fiction, but the writers were heavily influenced by a Scottish urban legend.

The idea of being stranded with a group of violent individuals who want nothing more than to cause mayhem is a terrifying thought made worse by the knowledge that it could happen anywhere to anyone. The movie helped Wes Craven gain the footing he needed to layer create Freddy Krueger, who was also inspired by a supposedly real series of events.

Them (Ils)

Clementine trying to survive the night in Them.

Most people will triple-check their doors are locked at night. A subconscious fear many people have is that an intruder will enter their house while they sleep. There are plenty of home invasion movies that feed into this fear, but there is one that is inspired by a real couple who met their fate when a group of teenagers broke into their home.

Them seems like a run-of-the-mill home invasion movie on the surface, but the true story claim isn't the only thing that sends chills up viewers' spines. The randomness of the invasion and the pain the couple goes through is enough to make even the most seasoned horror vet squirm.

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