After a year away from working in the field, archaeologist Cormac Maguire and pathologist Nora Gavin are back in the bogs, investigating a ninth-century body found buried in the trunk of a car. They discover that the ancient corpse is not alone - pinned beneath it is the body of Benedict Kavanagh, missing for mere months and familiar to television viewers as a philosopher who enjoyed destroying his opponents in debate. Both men were viciously murdered, but centuries apart - so how did they end up buried together in the bog?