Laura and Owen's new home should be lovely. But soon after moving into the secluded cottage on the edge of the Peak District, Laura starts to hear faint snatches of birdsong. Her husband, wrapped up in his job, is rarely at home. Nervous and confused, Laura cannot decide whether the noise is real - or is coming from inside her head. Her doctor can find nothing wrong with her hearing. Then an archaeological dig on a neighbouring hill unearths some disturbing finds - and Laura's life starts to become terrifying.