Haunted Ground by Erin Hart
Two farmers discover the head of a woman in an Irish peat bog. An archeologist, a local detective, and Norah Gavin, an American pathologist, are called in to figure out where it came from. As they start digging—literally and figuratively—people begin to wonder if other bodies will emerge from the bog, particularly those of the wife and son of a local landowner, who have disappeared and are presumed dead. The unlikely team has to work together to solve two mysteries—one ancient and one very much of the present day.