July 1909: in Carcassonne a sixteen-year-old girl is given a book by her father which he claims contains the secret of the true Grail. Although Alais cannot understand the strange words and symbols, she knows that her destiny lies in keeping the secret of the labyrinth safe. July 2005: Alice Tanner stumbles upon two skeletons during an archaeological dig in the mountains outside Carcassonne. Inside the hidden tomb, she experiences an overwhelming sense of malevolence, as well as a creeping realisation that she can somehow understand the mysterious ancient words carved into the rock. Too late Alice realises she's set in motion a terrifying sequence of events.