Mrs. Aylwood is a distraught mother since her daughter, Karen, vanished in the Welsh countryside 30 years ago. When the Carstairs family move into the Aylwood manor for the summer., strange occurrences begin to unnerve the family and Jan begins to suspect that they are linked to Karen's disappearance. As Jan unravels the dark past hidden by the townspeople, she delves further into the mystery and deeper into danger, but now it might be too late to escape the Watcher in the Woods.