Wow. There is a lot to praise here.
The cinematography, score, and writing are all excellent. The acting is very strong, from Oksana Akinshina (who hasn't changed a bit since playing a minor but important role in The Bourne Supremacy) to Pyotr Fyodorov, nearly the entire cast is excellent. 4 out of 5 mainly because I have no benchmark. Hope to see more excellent films like this from Russia in the next few years.