During the New York City blackout of 2003, Kate, a struggling 30-something model with a troubled past, has just moved into her girlfriend Leah's Brooklyn loft, but already doubts about their relationship have begun to loom. When Leah leaves for the weekend, Kate unexpectedly finds herself alone in the apartment in the middle of the worst blackout in North American history. As darkness falls over the city, Kate's paranoia grows and she begins to believe someone in the building is stalking her. With no one to help her and escape out of reach, Kate is forced to confront her deepest fears as she fights to survive through the night.