The Cleaner.

Just out of prison, Tomáš, a taciturn loner, takes a job cleaning houses where people have recently died. Things take an alarming turn when he begins putting in overtime: hiding behind closet doors after hours to secretly watch the homes’ residents. His voyeuristic ways soon lead to a romantic obsession with a woman in distress—but in order to help her, Tomáš will have to come out of the shadows.