When a hard-working single mother, Sara Diaz, has her children taken from her after she is suspected of injuring her son, Ally Fisher, a recent law school graduate, is assigned to represent her case before Judge Martha Schulman, a veteran of the Family Court System.

Unaware that a serial killer is stalking clerks at 24-hour convenience stores, Debra reluctantly takes the night shift at her minimum-wage gas station job after her co-worker disappears. What begins as routine shelf-stocking and floor-sweeping quickly spirals into a heart-pounding descent into paranoia, dread, and blood-soaked madness as the killer closes in.