It's a french horror film (also known as Ils) about a couple living in a remote country house in Bucharest. One night they start getting terrorized by these things. Somewhat similar premise as The Strangers, but far superior. It's one of the scariest movies I've ever seen, and I don't scare to easily. It's just non-stop suspense from beginning to end. I'd highly recommend checking it out. And I'd also say don't read a single thing about it before you see it because there's a twist that some reviews might give away, and it's better off not knowing it beforehand.