On a stormy night in December, a tree is blown down on an isolated Devon farm. When the fallen tree is dragged away, a rucksack is found caught amongst the roots - and next to it is a human skeleton.

The discovery of the body and the rucksack revives memories for DI Wesley Peterson. A young hitchhiker who went missing twelve years ago was last seen carrying a similar backpack. Suddenly a half-forgotten cold case has turned into a murder investigation.

Meanwhile, in the nearby village of Petherham, a man is found dead in suspicious circumstances whilst staying at a local guesthouse. Wesley's friend, archaeologist Neil Watson, is studying Petherham's ancient mill and uncovering the village's sinister history. Could the string of mysterious deaths in Petherham over a hundred years ago be connected to the recent killings? As Wesley digs deeper into the case, it seems that the dark whisperings of a Burial Circle in the village might not be merely legend after all...