Sir Geoffrey de Mappestone, a brave knight of the Crusades, returns from a desert patrol and finds a fellow soldier murdered in a baker's bedchamber. But this is not the first suspicious death in the city -- other knights, and even monks -- have been killed, and Sir Geoffrey is certain that the murders are all connected. It is not long before he finds himself drawn into a sinister and complex plot to seize power in the Holy City -- and learns that his closest friends could also be his closest enemies.