The premise is simple enough: a young woman has sex with her boyfriend and some creepy, supernatural thing slowly follows her wherever she goes. If this supernatural monster thing catches her, she's dead. You can stop this "person" from following you, but you can prevent it from killing you by having sex with someone else. In lesser hands, this is a premise that could easily fall flat on its face. But director David Robert Mitchell really crafted something special here. It's taken seriously enough to garner palpable tension, but the characters have a lot of funny asides and quirks. This is going to be one of those movies where the more you watch, the more you find other things about the movie's world that you enjoy.
"It Follows" is so tense and clever that towards the end of the movie you keep looking in the background of the frame, wondering if there's someone slowly walking towards the screen. It's really hard to explain how effective this is if you haven't seen the movie, but the point is, it always keeps you on your toes. It keeps you engaged with the screen even if you want to look away.
The movie filled me with never-ending dread from the beginning. That's way more effective to me than just scares, though the movie didn't disappoint there either. It was visually compelling, and goddamnit, it was fun. My favorite types of horror films are the ones where I feel like I'm in good hands. That was definitely the case here.