Leighton Trent’s review published on Letterboxd :
It's nice to see some reinvigoration in the Monster genre. What the film excels at is what is lost on modern shock freaks: the unseen is scarier than the seen. You continually can't see the 360 degrees of what is going on and as a modern movie-goer it annoys you. As to the monster itself: it just slinks its way through the film and we don't get a really good look at it until the end. Sometimes you think you're going to get to see it, but it falls again into shadow, or the camera goes somewhere else.
There seems to be 9/11 evocations, but that's me probably reading into things.
The shaky cam was used to perfection here and whether you like it or not, it does not take away from the fact that it's effective (it doesn't bother me). And yeah, some cheesy stuff pervades the film, but that's what makes a geek movie great and is totally forgivable in the grand scheme of things.