Here we have an intuitive, polyrhythmic art form bridging cultures and titillating the young at heart. This definition could easily apply to baby-making or gang-banging, but in Doug Pray's trenchant documentary, it's "turntablism" distracting the passionate kids from reproducing and/or mowing each other down. Immersing us in the endlessly inventive, fiercely competitive world of hip-hop DJs, the project is sensational and revelatory, even if scratching makes you itch. By teaming up with the creatively titled "story structure writer" Brad Blondheim, director Pray (who helmed the grunge doc Hype! and edited American Pimp) breaks down cinematographer Robert Bennett's 40-plus hours of scintillating 16mm footage into digestible chapters, highlighting the history, methodology and energetic performances of the stylus superstars, including DJ Qbert, Mix Master Mike, DJ Shadow, the X-ecutioners and countless others. And then there's the ultimate, the touchstone for turntablists ranging from Cut Chemist to DJ Premier: jazz legend Herbie Hancock's 1984 single "Rockit," with the shwah-shwah and zicka-zicka-zicka that are, and ever shall be, a part of your nervous system. Enhanced by sound designer David Bartlett's Dolby Digital 5.1 mix, these countless little flicks of the wrist mercilessly attack the cochleae but admittedly sound very, um, fresh.