Medieval Florence lives taking advantage of the inventions and discoveries of the great Leonardo: printing presses print newspapers, steam-powered carriages move along the streets along with horse-drawn carriages, and mechanics armed with the latest invention of da Vinci, which allows you to instantly capture reality, are ready to compete with the artists’ workshop . However, the era takes its toll: conspiracies and murders still dominate the winding streets of the industrial city. On the eve of the visit of Pope Leo X, the assistant of Raphael, the most famous man in the entire Florentine Republic, dies at the hands of a mysterious killer. The key to the solution, the latest invention of the Great Mechanic, falls into the hands of the young artist Pasquale. Together with the famous journalist and detective Niccolo Machiavelli, he conducts an investigation, constantly finding himself in mortal danger. One bloody crime leads to another, and in the end the threat hangs over Leonardo himself. Now only an angel can save the brilliant master...