Alex Thompson’s review published on Letterboxd:
Does a lot of things very well. About as good a horror film as you're going to get that isn't also amazing. It's right up to that edge, though, and that's pretty darn good. Good actors (Wilson and Farmiga in particular sell the horror without the silliness always waiting to jump into performances like these), good story (a clever mix of pretty much every 70's horror film from The Exorcist to The Amityville Horror), and great direction from James Wan who does his best to make the movie feel of the 70s while also using some fantastic framing and moving camera techniques. Also, most importantly, it's super scary. Wan is a smart dude and knows that we as an audience know what kind of a movie we're going to see, so he'll not give us what we're expecting (a reflection in a medicine cabinet or a figure behind the doorway) right away. Instead he'll return to that idea a little later on and, built on the disappointment from the lack of scares earlier, give us the full whammy. It's quite a move. Of course, you can only do that kind of thing so often, and once this movie tips over the edge into a full fledged scarefest it's still very effective. There are some images and sounds that will stick with me for a while. Really good. Really really good.