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.

"All alone on your shift.... Or are you?"