If there's one thing that all horror movies have in common, it's that they aim to give their audiences an adrenaline rush, keeping them on the edge of their seats for the duration of the film, as they are plied with scare after scare.
But how is it that these movies are able to frighten their audiences despite only happening on screen? The answer is by executing a series of tropes that have been tried and tested over the years, with a very high success rate.
A trope is simply a convention that will be easily recognised by the audience as the film unfolds. They are devices without which it is impossible to tell a story, and often - when enough of them are used - create a formula for making great horror movies.
10. The Monster Under The Bed
This trope involves a very real, if not necessarily physical presence that well and truly frightens most of the film's characters. The monster in question will often make itself known by scratching windows, creaking the floorboards and so on. It will also be the film's antagonist.
In other words, the monster under the bed is the entity in a horror film that at least one of the characters might dismiss as being a childhood nightmare that nobody over the age of 7 should believe in. Like the Boogeyman, for instance. This character will undoubtedly be proved very wrong by the end of the film.
Trope Examples: Freddy Krueger - A Nightmare on Elm Street (1984), The Creeper - Jeepers Creepers (2001), Michael Myers (often compared to the Boogeyman) - Halloween (1978) and Bughuul Sinister (2012)