In August 1942, 22-year-old Jose Diaz was found dying near a Los Angeles reservoir called Sleepy Lagoon. He'd been beaten and stabbed the night before he was set to report to the U.S. Army. His death became the excuse the LAPD needed to launch a massive crackdown on Mexican American youth—rounding up 600 people, trying 22 young men with questionable evidence and igniting racial tensions that exploded into the Zoot Suit Riots of 1943. But who really killed Jose Diaz? And why did a fashion choice become a crime?