The film opens as Grady Edwards transforms himself in a bathroom. He shaves off his beard, dyes his hair, and takes out his brown contact lenses. He goes downstairs with his luggage, fixes himself a piece of toast with some peanut butter and drinks some coffee. As he leaves the house, the camera reveals the bodies of his wife and her two children. Throughout this scene string instrumented music is played to create tension and gets louder gradually, at the point were see the dead bodys of his family the background music increases immediately which make us the audience jump in shock.
The film comes to an end when Jackie hires a private investigator to look into David. Knowing his time is up, he goes to Jackie's house and brutally kills her by drowning her in her swimming pool on stormy night. He returns home and prepares to murder his new family and leave town. Determined to discover what was in the locked cabinets, Michael breaks into the basement as Kelly keeps a lookout. In the basement, Michael eventually discovers his father's body in a freezer, fear and tension is built in this scene as the audience awaits for Michael to get caught by David again fast camera movements give out the clue that something bad is about to happen. David knocks out Kelly and traps Michael in the basement. The commotion awakens Susan who enters the kitchen to discover Kelly unconscious and David furiously assembling murder weapons. He yells at her that it just is not working out, and that he thought she could be "Mrs. Grady Edwards". Stunned, Susan asks him to repeat the name. David grimaces and asks, "Who am I here?"
Realizing the danger, Susan runs upstairs. Michael escapes from the basement and revives Kelly. They follow David upstairs, where Susan stabs him in the neck with a piece of broken mirror. David chases them into the attic where he and Michael fight, eventually falling out of the attic and down to the ground, where they both lie unconscious. Michael comes out of a coma a month later. Kelly and Susan inform him that when the cops arrived, David had disappeared.
The film ends with a mother shopping in a home supply store with her two sons. She meets David who is an employee there. He introduces himself as Chris Ames. this leave the audience on a cliff hanger because we know what he is going to do next with this new family he has managed to get a hold of.