The other reviews are sufficiently clear and detailed so I'm not going to deepen. By cons I just wanted to confirm that this is one of the best comic "classic". I had read as a child and very dark story and drawings had already hit me. Reading one of the reviews I see that as my memories the whole story had not been published in France, and that is understandable because there is a big gap with the other comics of the time. Here we talk about the downfall of a man who ends up on the street, heroin addict and her friend, not to mention "Nuke" the great psychotic sick!
Mazzuchelli created boards of a beauty breathtaking, and the screenplay is brilliant, even if the end is not in my opinion the same ilk as the beginning (the descent into hell), hence, not 4 * 5.