This novel takes us to France of the 14th century, during the years when the Catholic Church waged a war of extermination against the heretics Albigensians. The Albigensian movement, or Cathars, which rejected the church hierarchy and the papacy, spread throughout southern France starting in the 12th century, drawing in both the nobility and common people. The inquisition court investigates the case of the Cathar heresy, consisting of Dominican monks, but the proceedings are cut short by a brutal murder of the senior inquisitor, Father Augustine. The search for the killer brings his subordinate, Brother Bernard, back to the tangled events of fifty years ago. On the path to the solution, Bernard not only learns the terrible secret of Father Augustine and discovers a traitor in his closest circle, but also meets his love.