Gary Davidson has seen better days. A sales executive struggling with booze and gambling, his job performance has slipped and he is given notice from his employer that he has 30 days to pick it up or he's out on the street. It doesn't help that he keeps hearing, 'Knock knock knock...Housekeeping!' In his apartment. At 3 in the morning. When no one's there. Ultimately his experiences escalate to disturbing paranormal interactions with the 'housekeeper,' driving Gary to the brink of insanity.