2Pac became the unlikely martyr of gangsta rap, and a tragic symbol of the toll its lifestyle exacted on urban black America. At the outset of his career, it didn't appear that he would emerge as one of the definitive rappers of the '90s -- he started out as a second-string rapper and dancer for Digital Underground, joining only after they had already landed their biggest hit. But in 1991, he delivered an acclaimed debut album, 2Pacalypse Now, and quickly followed with a star-making performance in the urban drama Juice. Over the course of one year, his profile rose substantial...