When I saw the trainers for it, I was thinking, "Aww, no, that's going to be painfully formulaic". And it was formulaic, to the point where they'd have had to try very hard to have made the plot any more obvious. But what I was wrong about was that this would be a bad thing.
Having the movie be so entirely predictable allowed the acting and dialogue to carry the whole thing. It was marvelously done.
-BP