This one of those films that just has you, that grabs you and doesn't let you go and when it gets rough it won't let you look away no matter how tempted you might be.
I utterly loved this. It's style was unforgiving. You're thrown straight in. There's no exposition, no unnecessary padding. Characters are carved quickly with effective dialogue, their behaviour leaving you a little uncomfortable, laying the groundwork for later. Then comes the green room in question and what follows is an impeccably well-paced and suspenseful story that had me enthralled until the credits rolled. It's a great example of every craft of film working in harmony.
Coincidentally, in the unbelievable period we find ourselves living in, this film serves as a reminder (a reminder most of us never need) that Nazis are the bad guys. Even when they're being played by Patrick Stewart. The methodology exhibited by these skin-colour-obsessed monsters is truly terrifying, made all the more scary by the fact that people carrying these attitudes are finding a resurgence right now. They've watched films, right? Surely they know they're the baddies?
You can't comment on this without noting the direction and the performances. Both were fantastic. Anton Yelchin's talent will be missed. It's a travesty that we won't get to see more from this man.