I am really jaded on horror movies, normally only listing The Exorcist, The Shining, The Ring, Insidious, The Mothman Prophecies, and The Fourth Kind as 100% awesome, but this movie in my view has done extremely well for itself. Well enough to be at least considered in the same company as the last two I mentioned.
The acting was good. Keri Russell had the most to sell and she did a very very good job as a youngish suburban mother with underlying struggles in her marriage, and two kids who have their own seemingly minor issues that increase in volume as the film progresses, all living in a neighborhood that seems like it might have been the backdrop for that 80's Madness song Our House. Things in this movie mount as does the unease and freaky unexplained behavior as it should in a great atmospheric horror film and everything that happens seems very authentic and not way over the top. Making it seem as though there are definitely forces acting against this family but that they are probably not demonic or supernatural.
As things go farther and farther out of control and the manifestations go from manipulation of environment to manipulation of the bodies of the family itself, the score, acting, direction, and atmosphere keep up well. Not with stupid jump scares that seem contrived, but with genuine shock moments that make the viewer feel right in the shoes of the characters and feeling their senses of disbelief and mounting fear. When the hopelessness of the truth finally reveals itself, and after the requisite battle for rationality fails, the end game is about as harrowing as one could hope for and delivers very much in the same vein and with the same methods as some of those aforementioned movies, plus others such as Sinister and Paranormal Activity.
People will probably be able to pick out those techniques in this movie, and some might say they are just all thrown together with a common fallback trope over the top to try to give it a twist, but sometimes in a genre where it's very hard to be original these days one has to judge by how well those elements are all brought together and call that its own sort of originality or at least uniqueness and I felt that was the case with this movie. Very good choice for lights out Saturday couples movie night and even better solo.