Every night, she cleans. On the fourth floor of an unnamed office in an unnamed city, the night cleaner comes and does what she does best--sorts out the messes of the daytime employees. None of them know her, but she knows everything about them: Sad Intern's dreams to get promoted, Résumé Woman's nasty flight-risk behavior, Mr. Buff's secret smoking habit... After all, protecting the employees is her responsibility: whether it's from rats and window smudges or from the sinister CEO who may be driving the company into ruin.