Lakeview Terrace (2009)

A young couple has just moved into their California dream home when they become the target of their next-door neighbour, who disapproves of their interracial relationship. A stern, single father, this tightly wound LAPD office has appointed himself the watchdog of the neighbourhood. His nightly foot patrols and overly watchful eyes bring comfort to some, but he becomes increasingly harassing to the newlyweds. These persistent intrusions into their lives ultimately turn tragic when the couple decides to fight back.

Official website: http://www.sonypictures.com/movies/lakeviewterrace/