The first 45 minutes are quite intense, the whole setup just works fine and the simple but effective cinematography is nice to watch. Though I was not really convinced by Speedman's attempt to reflect intense emotions, you can always rely on Liv Taylor, who is - given a rather thin piece of script - really working her ass off to get the most out of it. Congratulations for that. The mocking "Strangers" start off being quite scary and the concept seems to be somewhat more original then we probably got used too, so it all seems like we're going to have a good time, but then suddenly everything freezes in the most inelegant manner, as the makers seemingly just ran out of any kind of idea how to continue this promising movie. That means, there is almost literally NOTHING new happening from around minute 45, it feels writer and director Bryan Bertino had half a decent script and then needed to finish it in about 2 hours due to a deadline or something. So the other 45 minutes are basically prolonging 2 jump scares and 3 lines of really basic dialog with minimum creativity, like lights turning off and the after a few minutes on again for no obvious reason, till the point where some kind of climax should occur, which then never really happens. Instead we get something really unrefined and boring featuring not a bit of fantasy, it's just like no one really cared anymore.
I'd recommend though watching the first half of the movie and then striding around in some dark forest for a while, that surely does the job much better. 4/10