The powerful Medicis commission rising artisan Leonardo da Vinci to create an Easter spectacle in Florence; Leonardo takes on another assignment to engineer war machines; the arrival of a mysterious Turk intrigues Leonardo.

Leonardo continues his quest for the Book of Leaves; the pope's nephew arrives; the failure of Leonardo's war designs causes a rift with the Medicis; the pope learns of Leonardo's talents.

Riario discusses his defeat with the pope and a mysterious prisoner; Leonardo searches for an explanation when the Medicis are blamed for an outbreak of demonic possession at a convent.

Bechhi is accused of spying for Rome; Leonardo reveals his latest weapon as the armies of Rome and Florence face off.

Lorenzo orders Piero da Vinci to defend his estranged son in court; Leonardo surprises the corrupt judge during a performance for visiting royalty; the Turk visits Leonardo at his workshop.

The Turk's clue regarding the Book of Leaves leads Leonardo to Wallachia, where he meets Vlad Dracula; Lorenzo and Piero encounter the Duke of Urbino; the hunt for the true spy continues.