First time we see Nick's apartment. Seeing the set for the first time, George Eads expressed concern about how high school it looked with too many trophies and books. The set dressers removed some of the props to make it look it more like a bachelor pad.
The trivia item below may give away important plot points.
Uses imagery and inspiration from the movie "Black Christmas." These include a shot of an eyeball in a door crack, a girl going into a closet and being smothered with a plastic bag, the killer in the attic and of course, "The calls are coming from inside the house!!"