The Intruder is a psychological thriller planned to hit theaters this spring. The story follows a married couple who moves into a new house — but the old owner does not leave that easily. Judging by the trailer, this film is going to make audiences feel uneasy about going home from the theater. Here are the main reasons why the concept is so scary: The storyline is alarmingly realistic. Unlike most horror movies, there aren’t any ghosts or supernatural creatures…