After a comet causes a radiation storm on Earth, machines come to life and turn against their makers. Holed up in a North Carolina truck stop, a group of survivors must fend for themselves against a mass of homicidal trucks. A diner cook, Bill Robinson, emerges as the unlikely leader of the pack, attempting to find an escape plan for himself and the survivors, who include his boss, Bubba Hendershot, and a newlywed couple.