When rock and roll was transforming American culture in the 1950s and '60s, East Harlem pulsed with the sounds of mambo and merengue. Instead of Elvis and the Beatles, Marta Moreno Vega grew up worshiping Celia Cruz, Mario Bauza, and Arsenio Rodriguez. Their music could be heard on every radio in El Barrio and from the main stage at the legendary Palladium, where every weekend working-class kids dressed in their sharpest suits and highest heels and became mambo kings and queens. Spanish Harlem was a vibrant and dynamic world, but it was also a place of constant change, where the traditions of Puerto Rican parents clashed with their children's American ideals. A precocious little girl with