A delicate truce between Milan and Florence is disrupted. Lorenzo de Medici's dilettante brother Giuliano suggests an Easter celebration as a show of power and commissions the rising artisan Leonardo da Vinci to create a spectacle at the event. After some maneuvering, da Vinci is commissioned to sketch Lorenzo's mistress Lucrezia Donati. Meanwhile, Pope Sixtus IV hears of the successful assassination of the Duke of Milan and the brilliant war engineer hired by Lorenzo. Leonardo is intrigued by a mysterious Turk that appears in Florence.