John Fairchild is a lonely retiree breaking his silence on an event that happened several years earlier. Soon after moving to a Virginian suburb, John meets Mary, the little girl next door. John finds Mary in her backyard one morning screaming at someone who is not there, and as she begins to calm down he hears footsteps as if a person is running past him. After he finds evidence that his home is broken into while he is sleeping, John becomes paranoid until Mary shares a secret with him that pushes him over the edge: contrary to his belief, he does not live alone. A few strange occurrences and some experimentation start to convince him Mary is telling the truth, and then one night he comes across a clue that brings him face to face with a horror 400 years in the making.