20 Most Underrated Horror Movies EVER

13. Black Christmas (1974)

Though absolutely highly rated by those who've actually seen it, it's fair to say that 1974's original Black Christmas has never received the love it's so thoroughly deserving of.

Notably, Bob Clark's proto-slasher film predated John Carpenter's Halloween - which it ultimately influenced - by an entire four years, even if it's Carpenter's film which of course went on to define the slasher as we know it.

Much as the concept of a group of sorority sisters being picked off by a shadowy killer might seem tired today, Black Christmas basically invented it, and more to the point, Clark was far more interested in atmosphere and suspense than over-the-top blood-letting.

Rather than bash viewers over the head with excessive characterisation for its antagonist, it instead lets him exist as a vaguely defined force-of-nature, as ultimately only makes him that much more terrifying, all the way through to what remains one of the genre's most chilling endings.