Hip-hop has always been a puzzle, and the two-CD "platinum edition" of 1987"s classic Paid in Full reestablishes one of the genre"s key pieces in proper context by combining the original 10-song tour de force with a companion collection of important remixes. From Eric B."s Technics terrorism and sampling symphonies to Rakim"s soulful, street-smart flow, Paid in Full is landmark science, a Ph.D. effort building on the early theories of New York City legends like the Sugarhill Gang and Grandmaster Flash. By featuring 10 remixes--including Coldcut"s "Seven Minutes of Madness" treatment of the title track and the Wild Bunch"s "Move the Crowd"--The Platinum Edition also highlights the duo"s influence on DJ and club culture beyond the B-boy set. --Mark Woodlief