In present-day Manhattan, four masked horsemen dressed as Templar Knights stage a bloody raid on the Metropolitan Museum of Art during an exhibit of Vatican treasures. Emerging with a strange geared device, they disappear into the night. What follows is an investigation that will draw an archaeologist and FBI agent into the dark, hidden history of the crusading Knights-and into a deadly game of cat and mouse with ruthless killers-as they race across three continents to recover the lost secret of the Templars.