Barbarian

Barbarian is a Horror / Mystery movie where common sense exits early and everyone else is left to deal with the consequences. The IMDb crowd seems broadly convinced, which is more than can be said for a lot of modern entertainment. Expect the obvious answer is, naturally, almost never the answer. It is not trying to solve cinema, cure society or earn a medal for restraint; it just needs the premise to work, the momentum to hold, and the audience to avoid checking the clock every six minutes.