"When a Russian computer virus jumps the species barrier, wiping out most adults, the world falls precariously into the hands of the next generation. In the wake of devastation, musical prodigy Oscar Fuentes is separated from his twin sister Cira. Without each other's support, stranded on opposite sides of the country, they're swept into rapidly-evolving networks of diverse teenage gangs. Can Oscar find his way back to Cira ... or will they both be lost forever, in a dangerous makeshift civilization that is mercilessly replacing the past?"-- Provided by publisher.