 The only clue regarding her death is the word "Psalms", which is written in blood on the lid of the casket.D'Eon de Beaumont, Lia's younger brother and a knight in service of King Louis XV, takes it upon himself to investigate his sister's mysterious death, along with the strange disappearances of a number of French women.By order of the King of France, he is to recover the Royal Psalms which is linked to the mysterious death of his sister and the case of the missing women.