Archaeologist Clare Hills is struggling to finance her recently established university research institute along with her long-time friend, Dr David Barbrook. When Professor Margaret Bockford finds the Hart Unit work with a housing developer in the Cotswolds, the pair are hardly in a position to refuse. There is just one catch: the previous site director, Beth Kinsella, was found hanged on-site, surrounded by mutilated wildlife. Despite initial misgivings, Clare leads a team to continue work on the dig, but with rumours about Beth's mental state and her claims that the site was historically significant, progress is impeded at every turn. When one of the workers finds something unsettling, Clare suspects there may be more to Beth's claims than first thought.