Behind Gangs of New York is a fascinating yet neglected history. There is much artistry to be admired in this film, from its well-researched expansive set design and photography, to detailed minor props and costumes, but mainly it's the accurately vicious and corrupt portrayal of a forgotten era that is the main standout. The blu-ray is gorgeous and well-worth viewing, despite the epic film's possible flaws (i.e. questionable casting, or nonexistent physical changes despite the passage of 16 brutal years). As bonus material, there are a number of featurettes including the discovery channel special, "Uncovering The Real Gangs of New York", which verifies the film's depiction, and references its real life characters. Additionally, there is a commentary by director Martin Scorsese who is himself, a walking film historian and reference guide.