This doc is an absolute must for hip-hop fans. If you are the kind of person who hates the sound of scratching, or thinks that sampling is artistic thievery, this movie won't change your mind. But if you want to know the history of this weird post-modern rhythm instrument--as it relates to rap and as a percussion tool, this is perfect. The movie lacks a good discussion of the issue of sampling (it is given a short gloss-over in the extras) which is one of the more interesting aspects of the dj craft. Also it would have been great to see and hear a wider variety of deejays, like Terminator X, Hurricane, and Jam Master Jay, but the documentary was more interested in the culture of the dj as a solo performer. Despite its faults, this is one of the most entertaining and enlightening music documentaries I have seen lately.