Two hundred thousand people flood downtown Los Angeles to join an anti-violence protest march.    One has come to kill.    This hyper-drive, fifth-gear thriller chronicles the day when the unthinkable happens: An ACTIVE SHOOTER penetrates the security perimeter, kills several Police Officers and barricades himself in an abandoned building where he takes up a rooftop nest to kill more cops.    Chief Negotiator Tom Cody is the outcast pariah of the LAPD tasked with stopping this one-man killing machine. For every new police casualty, the true motive slowly begins to emerge, and the LAPD’s darkest, most well-guarded secrets begin to unravel…