Trivia: Spoilers. In the end, Dr. Butler and his wife Stephanie are revealed to be the killers. They were actually the killers in the original script for the first film, but the ending was changed several times until the final version seen in theaters with Lori being the killer. The original idea was recycled into this film, since the dimension-hopping angle of the story allowed the presence of a new version of the killer.
Trivia: The celebrity address app lists several famous fictional characters, including Jack Torrance from "The Shining" and Tyler Durden from "Fight Club."