On the shore of the picturesque Belon River, in an area where world -famous oysters are grown, a stubborn aging actress of a man's corpse discovers. Just a little later, the Commissioner will receive a Dupin report from the legends of the hills of Monts d´ Arrée, from the region of rumors about fairies and the devil. There was also a dead person whose identity did not know the police. When the Commissioner discovers that traces lead to mafia, Celtic brotherhoods and mysterious druid cults, this will begin to suspect that this will be his most bizarre case ...