The head of a young red-haired woman has been found in an ancient Irish bog. The provincial town of Donnegal is shocked by this terrible and intriguing discovery. Archaeologists Cormac Maguire and Nora Gavin are visiting the site. The results of their examination inexplicably turn out to be connected with the police investigation about the recently missing wife and child of the landowner Osborne. The secret of confession, the confession of a clergyman hundreds of years late and a ritual murder... Why does the revelation of long-standing historical secrets turn the main suspect into a victim of family intrigue?..