The Ulitmate Noir - WillTurner
Noir in French literally means "black" and that sums up Sin City quite nicely- this is as dark as it gets and no more so than in this.
Whilst the treatment of the central female character is questionable, this is often the convention of the noir genre and to be honest you either take it or leave it.
The central plot though of a good man corrupted by his desires is undeniably powerful and Miller extracts every ounce of tension from it.
In short, while certainly not for the squeamish, I heartily reccomend it.