You and your husband are home alone late at night, enjoying a romantic and intimate evening. You're having a pleasant and tender conversation, when suddenly, a sudden knock at the door interrupts the peaceful moment. Both of you jump up, startled, as you both look at the door. A knock repeats, but this time, much louder. It's loud enough to send shivers down both of your backs. You look at each other nervously, not quite sure what to expect.