The Missing Corpse (Brittany Mystery, Bk. 4)

Along the picturesque Belon River, home of the world-famous oyster beds, amid steep cliffs, ominous forests, and the Atlantic Ocean, a stubborn elderly film actress discovers a corpse. By the time Commissaire Georges Dupin arrives at the scene, the body has disappeared. A little while later, he receives a phone call from the mystical hills of Monts d'Arrée, where legends of fairies and the devil abound: another unidentified body has turned up. Dupin quickly realizes this may be his most difficult and confounding case yet, with links to Celtic myths, a sand theft operation, and mysterious ancient druid cults.