The Thing (1982)
No, we're not talking about that trash 2011 remake. John Carpenter's 1982 classic, which has definitely secured its place in the horror canon, is actually a remake of 1951's The Thing from Another World. There are so, so many reasons The Thing is iconic. It's a master demonstration in practical effects, and there's something to be said about the paranoia and dread that grow more and more palpable as the film progresses.