A woman vanishes in the fog up on "the Hill," an area locally known for its tranquility and peace. The police are not alarmed; people usually disappear for their own reasons. But when a young girl, an old man, and even a dog disappear, no one can deny that something untoward is happening in this quiet town. Young policewoman Freya Graffham is assigned to the case; she's new to the job, compassionate, inquisitive, and dedicated. She and the enigmatic detective Chief Inspector Simon Serrailler have the task of unraveling the mystery behind this gruesome sequence of events.