The Crossing Places is the first in the Ruth Galloway series by author Elly Griffiths. DI Nelson has been trying to solve the mystery of the disappearance of Lucy Downey over ten years ago. Somebody is sending Nelson cryptic messages about the disappearance. Then some bones turn up where anthropologist Ruth Galloway is digging and Nelson turns up expecting them to be the missing girl, although the turn out to be over 500 years old. Nelson enlists Ruth to help him solve the riddle of the cryptic clues taking them on a search that will put their lives in danger.
What I think Elly Griffiths is attempting to achieve here is the British Temperance Brennan.