Anton Yelchin
I know it's very easy to say but I had this opinion way back when and it was confirmed when I watched it again a couple of days ago. I really like how Anton acted in this film. He's not going to win an Oscar but I thought he played a human-being caught in the middle of a horrifying situation PERFECTLY. When he's telling the paintball story, it comes off as if Anton really played paintball with those guys. Things like that really sell a performance for me, not if they can do a good freak out scene or not. I'm really going to miss Anton because I feel this was the first of many films in the crime genre for him (my favorite genre)
R.I.P Anton Yelchin