In the 1960s, horror movie makers developed some interesting techniques to frighten the pants off moviegoers. The most shocking scary films of the time pushed the boundaries when it comes to delving into subversive content. This content ranges in tone from psychosexual terror to splatter-gore fun.

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While some leave much to the imagination, other directors whose movies are highlighted below don't shy away from reveling in gore and excess. Even with censorship laws in place for most of the decade, these films set the standard for astonishing and upsetting audiences. Without these startling features, modern horror might look a lot different.

1960: Peeping Tom

Michael Powell's Peeping Tom

While Michael Powell's Peeping Tom deals with a lot of same subject matter as another film released in 1960, Alfred Hitchock's PsychoPeeping Tom was met with much more controversy than PsychoPsycho was nominated for Oscars, while Peeping Tom was critically derailed and censored in many countries.

The movie stars Carl Boehm as a serial killer who targets women in London, using his portable camera to record his heinous acts. Now considered a very important proto-slasher, Peeping Tom's reputation (as well as Powell's) has evolved with time.

1961: The Pit And The Pendulum

Vincent Price in The Pit And The Pendulum

Based on the Edgar Allan Poe story of the same name, The Pit and the Pendulum stars Vincent Price as a madman in 16th century Spain obsessed with torture and death. With Roger Corman at its helm, the movie delves into psychotic, bombastic terror set within the confines of an expansive, haunted mansion.

As the movie reaches its shocking climax, Price's character Nicholas Medina uses the torture chamber within his castle to drive everyone from his own wife to his brother-in-law insane. Stephen King, in his book Danse Macabre, describes the end of The Pit and the Pendulum as "a return to an all-out effort to terrify the audience ... and a willingness to use any means at hand to do it."

1962: The Horrible Dr. Hichcock

The Horrible Dr. Hichcock

This Italian horror feature starring Barbara Steele and Robert Flemyng deals with a subject considered taboo even by today's standards: necrophilia. Somehow, Riccardo Freda's gothic horror film made it through the board of censors without any required edits or changes.

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Flemyng plays the titular Dr. Hichcock, a man who accidentally kills his wife during a forbidden carnal experience. When he returns several years later with his new spouse, the ghost of his dead first wife haunts the corridors of his elaborate, stylized mansion.

1963: Blood Feast

a man stands before a large statue from Blood Feast

The violence hinted at in Psycho paved the way for over-the-top gorefests in movies like Blood Feast. Directed by Herschell Gordon Lewis, the king of the splatter film, Blood Feast follows an Egyptian immigrant in Miami who sacrifices women to the ancient goddess Ishtar - hopeful his offerings will revive her.

Despite its low budget and focus on carnage, Blood Feast was a box office success. Entries like this one influenced some of the more extreme subgenres of horror.

1964: The Flesh Eaters

The Flesh Eaters

Another extremely graphic horror movie, The Flesh Eaters maintains a cult following due to its gruesome special effects. Jack Curtis's flick combines sci-fi monsters with post-WWII paranoia about Nazis hiding out around the world.

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When a small passenger plane is forced to stop on a remote island between New York City and Cape Cod, the plane's inhabitants discover the island is occupied by a Nazi scientist developing a solvent for human flesh using ocean life. These microbes, when activated, can dissolve the flesh of an entire person in minutes.

1965: Repulsion

Catherine Deneuve in Roman Polanski's Repulsion

Roman Polanski moves into uncharted psychological horror territory with Repulsion. Catherine Deneuve plays Carole, a young woman suffering from androphobia - an intense fear of interacting with men.

When Carole's sister leaves her alone in her London apartment for a long weekend, Carole's phobia gets worse, leading her into terrifying hallucinations and dissociations that culminate in a ghastly final act. By visualizing Carole's frightening descent into madness, Polanski makes nightmares feel real in his film.

1966: Kill, Baby... Kill!

Kill, Baby, Kill

It doesn't get much more shocking than a little girl engaging in a murderous rampage through a small Carpathian village. Mario Bava's Italian horror classic Kill, Baby... Kill! is a period film that relies on foggy exteriors, mood lighting, and screeching winds to amplify fear in its viewers.

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When a pair of science-minded outsiders investigating the murders discover the vengeful spirit of a young ghost is responsible for the deaths in town, they desperately try to figure out how to appease the tyke. They are forced to turn toward magic and superstitious rituals to save the village's inhabitants.

1967: The Sorcerers

Boris Karloff in The Sorcerers

Toward the end of his acting career, Boris Karloff starred in Michael Reeves's spooky exploration of aging The Sorcerers. Karloff plays Professor Marcus Monserrat, a medical hypnotist who develops a technique that allows him to control the minds and share the sensations of his subjects.

The professor and his wife Estelle soon live vicariously through a 20-something man named Mike, but their obsession with feeling young again takes a toxic, unsettling turn. The Sorcerers melds psychedelic, garage rock aesthetics with incredibly serious commentary about what it means to be elderly in contemporary society.

1968: Night Of The Living Dead

Ghouls in George Romero's Night of the Living Dead

George Romero's bloody, obscene zombie film remains among the best of its kind. When it was released in 1968, Night of the Living Dead pre-dated the MPAA rating system by one month, meaning moviegoers of all ages - even kids - were exposed to this macabre story about a zombie apocalypse in rural Pennsylvania.

Using real animal parts to make it look more realistic, the movie revels in watching its ghouls feast on their victims. Night of the Living Dead's exploitation-style debut went on to become one of the most profitable horror movies of all time, even though it sensationalized audiences all over the world.

1969: Horrors Of Malformed Men

Horrors Of Malformed Men

This Japanese movie from Teruo Ishii is a transgressive, groundbreaking work of horrorHorrors of the Malformed Man follows a young medical student named Hirosuke who assumes the identity of a dead man who could be his identical twin.

From there, Hirosuke travels to a bizarre island where the dead man's father Jogoro conducts hideous experiments on people. The web-fingered Jogoro hopes to create an ideal society for himself, one where abnormalities and disfigurements are commonplace.

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