This is probably the most underrated movie that I have ever watched. It should have nothing but 5 stars for it's unique way of story telling where a spy story is depicted in it's realistic way and not as a larger-than-life avatar.
There are some raw edges but I have watched this movie a few times(yes, I liked it so much) and that rawness in fact suits well with the characters being from Bihar and it's officers. That rawness makes the characters feel real, original and sweet.