First off, I feel like it was a big mistake to make the killing of Peter so vague. I get that the director wanted the viewer to focus on the atmosphere and the tension in the film, but then to drop the bombshell at the end it was a complete sidestep in the direction she had us going. Yes, plot twists can be awesome, but the hints of what was going to go down were just way too subtle. Mentioned 1 word about anthrax, one time in the beginning. Showed 1 millisecond of a cut on a ranchers hand. Showed ZERO signs of Peter being capable of murder or even planning a murder. I'm supposed to connect the dots with that? It would have been way more intense if they would have at least explained what happened or made the clues a little less subtle. The running to google route was very anticlimactic for ME. But yes it was cool too have the feeling of thinking Phil was gonna murk Peter this whole time, only to have the okey doke pulled on me at the very end, just wish it was handled a little better. Long winded explanation about a small gripe, I know.
Secondly, the actor who played Peter did a fine job. Probably Oscar worthy performance. But then I got to thinking how if Paul Dano was his age for this role, he would have blown that performance out of the water. So I'm feeling like there could have been a few different actors in that role that could have put in a better performance and made this movie an absolute lock BP.