The mountains of Carcassonne have kept a great secret for centuries... The secret of the disappearance without a trace of the last heretical Cathars who survived the bloody Albigensian wars, and of the Holy Grail, the guardians of which, according to legend, they were. Historians have been trying to uncover this secret for many years. But no one has ever come as close to solving it as Alice Tanner. It was she who made an amazing discovery while conducting excavations in the very heart of the underground labyrinths of Carcassonne. This discovery can turn many scientists’ ideas about the Cathars upside down or... it will cost her her life. Because powerful people with strength and power are ready to do anything to solve the mystery of the “Cathar Grail” » remained unsolved.