A wave of mysterious murders committed by a cold-blooded, super-powered killer is cutting a swath through Central City. But that's just the start of the grisly problems disrupting Barry Allen's neat, well-ordered world as he and his loved ones become the target of mysterious foes who will stop at nothing to get rid of his straight-arrow interference in their lives. How are the cases connected? And is even the Flash fast enough to solve the dual mysteries before another person dies?
