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The horror genre goes back as far as the beginning of films themselves, over a 100 years ago. Some of the earliest horror films were Gothic in style which meant that they were usually set in spooky old mansions, castles, or fog covered, dark and shadowy locations which created an air of mystery as usually what the audience can't see is the thing that is the most terrifying. The main characters were usually 'unknown' humans, supernatural or grotesque looking creatures. This included vampires, evil madmen, devils, ghosts, monsters, mad scientists, demons, zombies, evil spirits, Satanic villains, demonic possessions and werewolves. Horror films at that time were developed out of a number of sources: folktales, fables, myths, ghost stories, melodramas and Gothic/ Victorian novels from Europe, such as the work of Mary Shelley or Bram Stoker.
The first horror movie, only about two minutes long, was made by imaginative French filmmaker Georges Melies, titled Le Manoir Du Diable (aka The Devil's Castle) (1896) - which contained some elements included in later vampire films.
By the early 1930s, horror entered into its classic phase in Hollywood - the 'true' Dracula and Frankenstein Eras. The studios took dark tales of European vampires and undead aristocrats, mad scientists, and invisible men and created some of the most archetypal creatures and monsters ever known for the screen. Universal Studios was best-known for its pure horror films in the 30s and 40s, horror's classic characters (Frankenstein, Dracula, The Mummy, the Invisible Man, and the Wolf Man) and its memorable horror stars, such as Bela Lugosi.
Many of the films in the horror genre from the mid-1930s to the late 1950s were B-grade movies, inferior sequels, or atrocious low-budget 'gimmick' films. In the atomic age of the 1950s, 'modern' themes like effects of radioactivity exposure, toxic chemical spills, or other scientific accidents were explored.
Horror films branched out in all different directions in the 1960s and after because the Production Code disappeared and film censorship was on the decline. Directors began to portray horror in ordinary circumstances and seemingly-innocent settings, which made the movies both more realistic and terrifying.
Alfred Hitchcock, whose early silent film The Lodger (1926) explored horror's themes, brought out some of horror's most 'horrific' films. His films changed the face of all horror films ever since. He created the idea of horror that could be found in the dark shadows of the human soul itself. That the murderer was not some horrific supernatural being, but rather a disturbed person who could easily be your next door neighbour, an idea that has horrified audiences ever since.
In the 1970s, the horror genre was subjected to violence, sadism, brutality, slasher films, victims of possession, and graphic blood-and-gore tales.
In the 80s and 90s many of the more successful horror films from previous decades spawned inferior, low-budget, slasher films. Most of these sequels or 'imitations' were exploitative and featured gory violence, graphic horror, 'teens in peril,' along with computer-generated special effects and makeup. A common storyline through out these decades was that of a homicidal male psychopath committing a string of gruesome murders on pretty, female victims. Many of these films told the tale of a vengeful murderer motivated by revenge and/ or sexual reasons, movies of this storyline include the Scream (1996-2000) franchise.