An ancient riddle, a broken vow - a modern-day quest for a medieval treasure. Australian-born Dr. Olivia Walker is an Oxford academic with a reputation as one of the world's leading Crusade historians and she's risked everything on finding one of the most famous swords in history - Durendal. Shrouded in myth and mystery, the sword is fabled to have belonged to the warrior Roland, a champion of Charlemagne's court, and Olivia is determined to prove to her detractors that the legend is real. Her dream is almost within reach when she discovers the long-lost key to its location in Provence, but her benefactor - Raimund Blancard - has other ideas. For more than a millennium, the Blancard family have protected the sword. When his brother is tortured and killed by a man who believes he is Roland's rightful heir, Raimund vows to end the bloodshed forever. He will find Durendal and destroy it, but to do that he needs Olivia's help. Now Olivia is torn between finding the treasure for which she has hunted all her life and helping the man she has fallen in love with destroy her dream. And all the while, Raimund's murderous nemesis is on their trail, and he will stop at nothing to claim his birthright.