Archaeologist Will Freeman is working on a dig in Southern France looking for links between modern France and the Cathar heresy. When his colleague is murdered Will becomes the focus of the police investigation. Coming under pressure from his family, the University and the French establishment Will is forced to abandon his research and take a job in Paris.Working to clear his name Will uncovers evidence of a shadowy organisation dedicated to locating the legendary treasure of the Cathars. When the pressure on Will is increased he has to make a choice between caving in and fighting back. Using his logical academic approach and enlisting the help of some unlikely people, Will sets out to turn the tables.As pressure on Will increases further he searches ever more desperately for a way to clear his name and is forced into one last, desperate gambit knowing that failure will result in the destruction of everything he holds dear.