Italy prepares itself for an attack from the Ottomans. Riario is been stalked by danger. Nico is the only person who can control what happens to Vanessa.
Clarice's life is in danger. The fellowship enters the Vault of Heaven, which holds many mysteries and deceptions. Lucrezia reaches her destination, meeting someone along the way.
Leonardo builds an underwater suit and breaks into the Vatican through the sewer. He meets the Pope and the mysterious prisoner. Giuliano reveals the identity of spy in Rome.
The Pazzis plan to overthrow the Medicis on Easter. The Turk tells Leonardo the location of the Book of Leaves. Later, Lucrezia admits a startling secrect, and Leonardo saves the Medicis.
Lorenzo manages to get back to the palace with the help of Da Vinci. Riario whereas continues on the voyage. The Pazzis are hanged for their conspiracy.
Leonardo reunites with Riario and Nico in the New World. Lorenzo attempts to save Florence with the help of an old flame. Clarice struggles to retain control of the Medici Bank.
As Leonardo and Riario prepare to die, Zoroaster and Nico plan their escape. Meanwhile, Lorenzo tries to meet with the king of Naples and Bayezid visits Rome.