It's Christmas Eve. The last employee to leave her office, ambitious corporate climber Angela (Rachel Nichols) arrives in the deserted parking garage only to discover her car won't start. She's relieved when Thomas (Wes Bentley), a seemingly friendly security guard, comes along and offers to help. Unable to get the engine to start, he invites Angela to share a small Christmas meal with him. She laughs off the invitation but it quickly becomes clear her situation is no laughing matter. Angered by her refusal, the psychopathic Thomas knocks her out and ties her up in his office. Coming to, Angela realizes that the only way she will live to see Christmas morning is to find a way to escape from P2.