While in Paris on business, Harvard symbologist Robert Langdon receives an urgent late-night phone call: the elderly curator of the Louvre has been murdered inside the museum. Near the body, police have found a baffling cipher. While working to solve the enigmatic riddle, Langdon is stunned to discover it leads to a trail of clues hidden in the works of Da Vinci -- clues visible for all to see -- yet ingeniously disguised by the painter.