In Los Angeles in 1991, Zack de la Rocha's barked lines met Tom Morello's toggle-switch guitar over a rhythm section that turned the protest into a dance beat.
In 1998, Q-Tip, Phife Dawg, Ali Shaheed Muhammad and Jarobi White replace A Tribe Called Quest's breakup with a one-year truce that leads to four more albums.
Riffs and Beats finds Tupac Shakur on a West Coast night street, bandana silhouette against purple neon, walking the block with the lines still in his head.