The Knights Templar and their supposed lineal descendants, the Freemasons, have been a fertile source of investigation for historians, scholars and writers of fiction. The mysterious and secretive organizations with their behind closed-door rituals, symbols and secret signs of recognition have fascinated people for centuries and led to speculation about the legality and morality of their very existence. When a jewel encrusted cross, the property of the Masons and allegedly once owned by the Templars, is stolen, it leads to a series of brutal and mystifying serial murders. Inspector Mag Goldman of the NYPD leads the team that is tasked with finding the identity of the killer and bringing him to justice. But because of the nature of the clues at the sites of the homicides point to a connection to the Middle Ages, Mag asks his friend Professor Bradley Davison of Queens College to help solve the crime. Dr. Davison, Chairman of the History Department and Director of the Center for Medieval Studies had already helped the NYPD solve five previous serial killings. Now, using his knowledge of arms and armor and the history of all things Medieval, Brad Davison must use all his talents to figure out the meaning of the clues to discover who is behind the many murders that have shocked the city.