Darron Aronofsky's polarizing take on the perils of drug addiction is one of the most difficult films to watch that has ever been made. The way that the characters gradually digress into addiction has such a realistic way about it that no other film has been able to capture quite as well. The believability of the characters is really quite tragic and Aronofsky makes full use of the audience's connection with these highly troubled people. The four main characters, Sara, Harry, Marion and Tyrone, seem like they could be your best friends, which makes watching them kill themselves with various types of drugs all the more harrowing. Aronofsky gives Requiem for a Dream a surreal touch that counter balances the stark realism to great effect and makes the film as visually appealing as it is depressing.
12. Alien
Alien is a film that has the ability to terrify audiences in many different ways, which makes it one of, if not, the greatest horror films ever made. H.R. Giger's set and alien designs provide the movie with some of the most striking imagery in film while the premise of Alien is simple yet brilliant. The narrative plays on humanity's inherent fear of the unknown, which subverts the typical science fiction premise of discovery by giving it a very dark twist. The Xenomorph itself works as a frightening movie monster but also as a symbolic representation of giving birth. There are few things that frighten people more than birth and Alien exploits that fear to genius effect. Ridley Scott wisely keeps the monster hidden in the shadows for the majority of the film, which always keeps a shroud of mystery around what it actually is. Alien is a film that uses so many unique ways to terrify the viewer that you will likely never forget it.