5 horror movies so gruesome, the makers were investigated for cruelty and murder

When you're sitting in a dark theater watching some particularly gory act of horror, it can be easy to forget that it's all just corn syrup and clever tricks. But every now and then, an especially ingenious special effect—or an especially gullible audience—has prompted police and courts to get involved. Here are five cases where audiences and the authorities became convinced that a horror film or film set might be evidence of a real violent crime.

A quick word of warning: I've kept the images in here quite tame, but if you go Googling these films, be sure you have the stomach for what you might find.

A Lizard in a Woman's Skin: While most of us will remember Carlo Rambaldi as the special effects man responsible for E.T., he was also involved in some less cuddly projects. Most notorious among them is A Lizard in a Woman's Skin, Lucio Fulci's 1971 LSD-fueled crime story about a woman who accused of murdering her neighbor after dreaming about the crime. In the film's most infamous scene, Carol, the possible murderess, walks into a sanatorium to discover four vivisected dogs, their chests open and their hearts still beating.

Rambaldi's effects were so convincing that an Italian court charged Fulci with animal cruelty, and the director faced a two-year prison sentence. The crew members testified that no dogs were vivisected in the making of the film, and Rambaldi had to trot in the animatronic creatures, made from rubber and coyote skins. The charges were eventually dropped, and later cuts of the film excised the dog scene. As for the actual prop dogs, Rambaldi supposedly destroyed them, finding they evoked distasteful memories.

5 horror movies so gruesome, the makers were investigated for cruelty and murder

Cannibal Holocaust: Although not the first film to fool audiences into thinking the on-screen gore was real, Ruggero Deodato's 1980 Cannibal Holocaust is probably the most famous. This early found footage film followed a documentary crew who had gone into the Amazon to film cannibal tribes. The documentary style of the film and the employment of real indigenous people as actors led some people to suspect that the on camera deaths were real. Following rumors that Cannibal Holocaust was a genuine snuff film, the film was confiscated 10 days after its premiere and Deodato was charged first with obscenity and later murder. (It probably didn't help that the four main actors had contract provisions demanding that they stay out of the media for a year.) Once again, cast and crew members had to appear before an Italian court to prove that their film's special effects were just that. Even after Deodato broke the actors' contracts and brought them onto an Italian television show, he still had to explain how he pulled off one of the film's disturbing impalement. Only then were the murder charges dropped.

While the human deaths were staged, Cannibal Holocaust did contain genuine footage of animals being slaughtered for the film (including a monkey being beheaded with a machete). The court found Deodato, the producers, screenwriter, and the United Artists representative guilty of obscenity and animal cruelty, giving them each a four-month suspended sentence. Recently, torture porn director Eli Roth claimed that he showed the film to a group of remote Amazon villagers—and they found it hysterically funny.

Guinea Pig: Flowers of Flesh and Blood: Manga artist Hideshi Hino originally produced the ultra-bloody, bad taste Guinea Pig film series as an adaptation of his own horror comics. The films, made throughout the 1980s, featured scenes of torture, mutilation, and murder that are at times so convincing (albeit over-the-top) that they've been repeatedly mistaken for genuine snuff. Guinea Pig gained particular notoriety in Japan in 1989, when one of the films was discovered in the home of famed serial killer Miyazaki Tsutomu. But most Americans likely learned about the gore movies in 1991, when none other than that paragon of clear thinking Mr. Charlie Sheen, convinced that Flowers of Flesh and Blood depicted a real murder (a gruesome dismemberment at the hands of a serial killer dressed as a samurai), contacted the FBI. The FBI launched an investigation—including tracking down and questioning the film's early distributor, Chas Balun—but dropped the case after watching Making of Guinea Pig, a documentary that explained the technical effects behind the first three films.

5 horror movies so gruesome, the makers were investigated for cruelty and murder

Snuff: This might be the only film on the list in which the marketers actively tried to convince the public that it was a true snuff flick. Low-budget film distributor Allan Shackleton had a turkey of a film on his hands, Michael Findlay and Roberta Findlay's Charles Manson-inspired Slaughter. Shackleton removed the film's credits and added a new ending. After watching the poorly produced Slaughter, the audience would see what appeared to be behind-the-scenes footage from the film. As the crew members begin to leave, several of them suddenly hold down a female crew member and brutally murder her, finally pulling her intestines from her body. If that wasn't bad enough, two crew members are heard talking in background, one shouting that they've run out of film, and the second demanding to know if he got the whole bloody scene. Once he confirms that he did, the film ends.

The movie was marketed with the tagline, "The film that could only be made in South America...where Life is CHEAP!" Variety exposed the marketing as a hoax, but persistent rumors prompted New York District Attorney Robert M. Morgenthau to investigate whether the film did, in fact, feature a real murder. Morgenthau had the police track down the actress who played the murdered crew woman and announced that she was, indeed, alive and well.

New Terminal Hotel: This direct-to-video horror flick, one of actor Corey Haim's final films, is a bit of anomaly on this list. As far as I know, no one watched New Terminal Hotel and accused it of being a snuff film; rather, someone stumbled onto a leftover set two years after the movie had been filmed. Firefighters were putting out a fire at the George Washington Hotel in Washington, Pa., when they entered a blood-splattered hotel room littered with alcohol bottles. Police Chief J.R. Blyth called the scene the most grisly he'd seen in his 35 years on the job. Detectives spent eight hours of overtime investigating before they realized the truth: a movie scene had been shot in the hotel room and the hotel owner decided to leave the room splattered with fake blood just in case the crew needed to do reshoots. One wonders how long he was planning to wait given that Haim passed away several months before the faux bloody room was discovered.