For centuries, the inhabitants of Barrowbeck, a remote valley on the Yorkshire-Lancashire border, have lived uneasily with forces beyond their reckoning. They raise their families, work the land, and do their best to welcome those who come seeking respite. But there is a darkness that runs through the village as persistently as the river.

A father fears that his daughter has become possessed by something unholy. A childless couple must make an agonising decision. A widower awaits the return of his wife. A troubled man is haunted by visions of end times.

As one generation gives way to the next and ancient land is carved up in the name of progress, darkness gathers. The people of Barrowbeck have forgotten that they are but guests in the valley. Now there is a price to pay. Two thousand years of history is coming to an end.