Trapped in the hotel of her husband's various business meetings, a woman finds herself adrift between lives when she is approached by a stranger with vivid memories of an affair with her that she can't remember. She's always sitting there with her husband. He's always getting up to take a meeting. The other man always comes and sits, the stranger, who always insists on his account of their past affair, and every time he does, it's more convincing.

While in the hospital for a tomography of the brain of his autistic daughter Sarah, Ben becomes upset when there is a power failure. He decides to leave the hospital with Sarah, while the nurse Emily tries to convince him to leave Sarah for further treatment. They get the elevator with three other passengers, and suddenly the elevator stops; when the door opens, people has vanished from the hospital, the environment is creepy and they are chased by devilish monsters. They find that they are trapped in the hospital, and the creatures seem to be hunting Sarah.