The 17 scariest horror movies based on true stories

Anyone with a passing interest in true crime is familiar with the Zodiac Killer, who terrorised San Francisco with a string of still-unsolved murders in the 1960s. But David Fincher’s chilling masterpiece is less about the slayings – though he re-enacts several of them in unnerving detail – than the rabbit hole the killer opened up with the maddening puzzles and coded messages he disseminated through the press. The case fully consumed political cartoonist Robert Graysmith, played by Jake Gyllenhaal, whose decades-long obsession with uncovering the Zodiac’s identity cost him his marriage. Given how, every few years, some new theory arises about who committed the killings, he’s clearly far from the only one.

One of the first horror movies to go hard promoting itself as a ‘true story’, Stuart Rosenberg’s tale of supernatural harassment is a sufficiently scary haunted house flick, but its legacy (and box office) is tied to its legend. According to the book it’s based on, in 1975, a family moved into a house in Long Island that had previously been the site of a grisly mass murder, and were subsequently driven out by malevolent spirits. Sceptics have long discredited everything but the murder part. But the movie was a huge surprise hit, effectively remaking the concept of possessed real estate for the American middle-class and influencing everything from Poltergeist to Paranormal Activity – plus several dodgy sequels.

Ed and Lorraine Warren were semi-famous paranormal investigators before director James Wan decided to turn their most well-known case into a throwback haunted house movie and made them perhaps the most famous ghost hunters in the world. Who else in their field can claim to have inspired the most successful horror franchise of all-time? The so-called ‘Conjuring Universe’ has spun off in several directions now – including the Annabelle movies – but the first film takes its inspiration directly from the Warrens’ account of investigating supernatural activity at a crumbling farmhouse in Rhode Island back in 1971. It gleefully mashes up numerous classic horror tropes, including many jump scares, and proved that Wan, previously known for the torture porn Saw franchise, could conjure up more than just nausea. 

Three years after The Amityville Horror, director Tobe Hooper effectively ‘Spielbergised’ the modern haunted house movie – with an assist from Steven Spielberg himself, who produced and possibly, maybe ghost-directed some of it – turning in a horror classic. And like Amityville, it takes inspiration from an actual haunting. In the 1950s, the curious case of the Hermann house in suburban Long Island became a national media story after the family brought in a paranormal investigator to diagnose unusual activity, such as randomly popping bottles and objects moving on their own. The house did not ultimately vanish into an interdimensional portal, however.    

The incident that inspired this indie thriller didn’t end in death or involve any sort of bloodshed, but it is nonetheless deeply disturbing – and not without torture. In 2004, a man claiming to be a police officer called a fast-food restaurant in rural Kentucky and managed to convince the employee who answered to strip search her coworker, the first in a series of rapidly mounting indignities. Craig Zobel’s claustrophobic drama doesn’t exploit the humiliation of what turned out to be an incredibly fucked-up prank call but uses it as a springboard to explore the American fealty to authority.

John Christie is perhaps second to Jack the Ripper as London’s most infamous serial killer, an unassuming postman who, in the 1940s and ‘50s, strangled at least eight women, including his wife, and hid their corpses in the walls of his Notting Hill flat. Richard Fleischer’s account of his killing spree is an under-seen gem of the true crime genre, featuring a truly chilling lead performance from Richard Attenborough, which the actor claimed haunted him for a long while afterward.  

It’s one of those scenarios your subconscious always seems to generate just as your moments away from drifting off to sleep: wouldn’t it absolutely suck to go scuba diving and end up stranded in the middle of the ocean? Americans Tom and Eileen Lonergan lived that nightmare in 1998, when the boat taking tourists out to explore the Great Barrier Reef accidentally departed without them. Whoops! How long they actually ‘lived’ is unclear – their bodies were never found. But filmmaker Chris Kentis has an idea of what happened to them, and it involves a horde of hungry sharks. Watching a helpless couple on the verge of becoming bobbing meat snacks doesn’t sound like much of a movie premise, but Kentis – who shot in the actual ocean, using real-live sharks – lends the incident a severely anxious realism that keeps your stomach sufficiently tied for 80 minutes.

Is it possible for a movie to seem too real? In its account of the so-called ‘barrel murders’ that haunted a poor Australian suburb in the 1990s, Snowtown lives alongside Henry: Portrait of a Serial Killer as a film that brings viewers a little too close to the darkest corners of humanity to qualify as ‘entertainment’. For seven years, a group of four men, led by John Bunting, carried out a series of gruesome slayings, mostly targeting alleged pedophiles and homosexuals. Director Justin Kurzel focuses particularly on how Bunting recruited an abused teenager into assisting him, and spares few details. No, it’s not something you casually throw on during a boring night in. But if you’re ever compelled to stare directly into the abyss of the human psyche, there may be no darker portal in movies.

Unlike practically everything else in his oeuvre, whose influence has only grown over time, Alfred Hitchcock’s most ludicrous film looks increasingly absurd with age, standing closer to The Blob or The Day of the Triffids than Psycho. But the story isn’t just some bizarre flash of inspiration he had after having his lunch stolen by a pigeon: in 1961, birds in the coastal town of Capitola, California, suddenly began dive-bombing homes and cars and vomiting up half-digested food. It took scientists years to determine that their mania was caused by toxic algae, and not any of the more metaphorical theories Hitch seemed to suggest: nature turning against man, female sexual repression, etc. In any case, for all its goofiness, it still managed to make the sight of a flock of seagulls standing together forever seem vaguely menacing.  

If the story of twin gynaecologists spiralling into shared drug-addled psychosis didn’t actually happen, David Cronenberg still would have invented it. He didn’t have to, though: in 1975, Stewart and Cyril Marcus were found dead in their trash-strewn New York apartment, likely from an overdose of barbiturates, an incident covered in both Esquire and New York magazine. Of course, Cronenberg being Cronenberg, he greatly embellishes the details, adding hallucinations of malformed genitalia, alien surgical instruments, a voluntary disembowelment and a central arc involving gross sexual coercion, making an already disturbing tale even ickier – as is his way.

A movie that is not, in strict genre terms, a pure horror film, the final feature from the great iconoclast Stuart Gordon becomes one by dint of the horrifying cruelty involved in the true story it’s based on. In 2001, a Texas nursing student struck a homeless man with her car, impaling him on her windshield. Instead of calling the authorities or taking him to a hospital, she left him there and drove home, where he died in her garage days later. Gordon adjusts the details of the incident to make it work as a bleakly comic thriller, but it still functions as a commentary on society’s indifference to the suffering of the dispossessed. 

True tales of circumstantial cannibalism abound, from 1993’s Alive to the more recent Society of the Snow. This one, partially based on the story of 19th century frontiersman Alfred Packer, is a tad exaggerated. Yes, Packer confessed to eating five members of his own party after getting lost in Colorado’s San Juan Mountains in 1874. No, he did not continue craving human flesh after being rescued. Packer’s experience inspired two other wildly embellished biopics, most notably South Park co-creator Trey Parker’s Cannibal! The Musical. But Antonia Bird’s film is the best of them, featuring a crazed, darkly comic performance from Robert Carlyle as Packer avatar FW Colqhoun. 

In the late ‘80s, the Mexican border state of Tamaulipas was terrorised by a group of so-called ‘narcosatanists’, a clan of drug-dealing occultists who practised ritual human sacrifice as a means of assisting their associated cartel. This effectively freaky indie horror flick dramatises the events surrounding the cult’s most widely publicised crime, the abduction and subsequent murder of a University of Texas medical student in 1989. While the film embellishes the details, a lot of it is more factual than you might think – a horrifying thought. 

In ultra-religious circles, exorcisms are, of course, a very real and not outmoded practice – even The Exorcist was loosely based on an actual incident – but The Exorcism of Emily Rose is more specific in its inspiration. In 1975, a young German woman named Anneliese Michel began experiencing seizures and hallucinations. At the behest of her Catholic parents, two local priests initiated dozens of exorcism rites until she eventually died from malnutrition. Her parents were then charged with negligent homicide. Director Scott Derrickson blends those facts with a liberal sprinkling of fiction, creating an interesting mix of psychological thriller, demonic horror and courtroom drama.

Obviously, a movie about alien abduction stretches the definition of ‘true story’, but former logger Travis Walton has never come off his insistence that on November 5, 1975, he was sucked into an extraterrestrial spaceship, violently probed, then deposited on the side of an Arizona highway. Regardless of the actual truth of the matter, the depiction of Walton’s abduction in this atmospheric chiller certainly feels real. It’s a frighteningly tactile experience: you see his captors in terrifying close-up, can practically taste the weird goop they force into his mouth, and the less said about the climatic ‘ocular examination’, the better.