Mark and Maggie's annual drive east to visit family has gotten off to a rocky start. By the time they're on the road, it's late, a storm is brewing, and they are no longer speaking to one another. Adding to the stress, Maggie—recently mugged at gunpoint—is lately not herself, and Mark is at a loss about what to make of the stranger he calls his wife. Forced to stop for the night at a remote inn, completely without power, Maggie's paranoia reaches an all-time and terrifying high. But when Mark finds himself threatened in a dark parking lot, it’s Maggie who takes control.