Harvard symbologist Robert Langdon is awakened in the middle of the night by a phone call while in Paris. The Louvre's elderly curator was assassinated within the museum, his corpse shrouded in enigmatic symbols. As Langdon and gifted French cryptologist Sophie Neveu comb through the strange puzzles, they are astounded to find a trail of clues hidden throughout Leonardo da Vinci's works—clues that are accessible to all yet cleverly camouflaged by the painter.