Wonderful character development!

I was totally surprised at how great this film.You could feel your paranoia rise as the film went on and as you gradually learned the details of the real situation.

Each character in this movie — down to the smallest one — is an individual rather than a type, prone to spontaneous changes of mood and sometimes amusing outbursts of pettiness or ill humor.

There are moments that feel comical, some horrific, and some downright inspiring but the tonal shifts hardly matter as the end results come to a film that's perfect for this time.