When shots ring out in a crowded L.A. club, bartender Harper Flynn watches helplessly as her boyfriend is gunned down in the cross fire. Then somebody throws a Molotov cocktail, and the club is quickly engulfed in flames. L.A. Sheriff Deputy Aiden Garrison sees a gunman in a hoodie and gas mask taking aim at Harper, but before he can help her a wall collapses. A year later, Harper is trying to rebuild her life. The investigation into the shoot-out has been closed. Certain that a third gunman escaped and is targeting the survivors, Harper enlists the help of Aiden Garrison, the only person willing to listen.