July 1099: sweltering in the merciless heat, Godefroi de Bouillon's desperate army finally breach the walls of Jerusalem. Concealed within their ranks are members of a secret fraternity. The Salt Lines seek a mystical artefact called the Keystone, and they're willing to sacrifice everything Godefroi values to possess it: the lives of his closest confidants, the only woman he has ever loved, even his very soul. With the veil of secrecy in tatters, truth has become the most dangerous possession of all.