They Trailer (2002)

They tells the story of a Psychology grad student named Julia (Laura Regan) and an event that turns her life upside down. As a child she experienced horrifying night terrors, but has seemingly overcome the problem. She reunites with a childhood friend, Billy (Jon Abrahams), and he tells her that he believes their night terrors are caused by something otherworldly and warns her to stay out of the dark, before suddenly committing suicide. At his funeral, Julia meets two of Billy's friends who slowly begin to believe his claims. Julia's night terrors return and she begins to doubt her perception of the world around her.