While working at Washington D.C.’s Smithsonian Castle, forensic linguist Joe Richmond is interrupted by a shocking early morning visitor. The Italian Ambassador was murdered in his Embassy at midnight, after sending a strange message in a cryptic photo. The picture leads Richmond, and brilliant cyber-security expert Gina Bocelli, to follow astonishing clues hidden in symbols linked to Machiavelli, Dante, da Vinci. They suspect their quest has drawn them directly into the biggest struggle of all time– involving a secret suppressed by mysterious murders and inquisitions over the centuries.

The danger increases when Richmond and Bocelli discover the dead Ambassador’s explosive fixation with two legendary ancient Roman Tribunes, whose legacy infused da Vinci’s Mona Lisa, Dante’s Inferno and Machiavelli’s Discourses. They find that ‘saper vedere’ or ‘knowing how to see’, is the key to unraveling the mystery. Richmond and Bocelli race through Washington D.C.’s museums, a monastery, and a New York City cathedral—to reach the astounding secret before the nameless pathological figure who will stop at nothing, can destroy it for all time.