Two intelligent headstrong heroines, 17-year-old Alais Pelletier from 13th century Carcassonne and modern-day PhD graduate Dr. Alice Tanner experience an adventure that intertwines their lives. Separated by time, but united in a common destiny, both protagonists display tremendous courage, steadfastness and loyalty on their respective quests.
As the parallel storylines set in the southwest of France unfold, both ancient and modern-day conspiracies are unearthed, all revolving around three hidden books - The Book of Words, The Book of Potions and The Book of Numbers. Together, these tomes hold the secret of the true Grail, which dates back to the Ancient Egyptian era many years before Christ.
Alais and those closest to her must battle to protect the secret. She soon discovers she can trust no one - least of all her cruelly manipulative sister, Oriane.
Back in the present day, Alice faces a race against time to put together the curiously familiar pieces of a jigsaw puzzle representing her long-buried history.