The Medici family suffers a great loss with the death of its patriarch Giovanni. When the designated heir Cosimo discovers that his father was poisoned, he decides to put Marco Bello on the assassin's trail.

The war is throwing Florence into chaos. Piero, Cosimo's only son, is eager to fight. Meanwhile, Cosimo manages to "buy" the withdrawal of Milan's troops, thus saving the city, but in the meantime Florence has again fallen into the plague.

Albizzi has managed to foment the citizenry against Cosimo, accusing him of the crime of usury. When Cosimo learns of the situation, he decides to return to Florence. Albizzi then invents a ploy to get Cosimo arrested and held for trial.

From prison, Cosimo asks Contessina to try bribing a member of the Signoria, to buy votes in his favor. Albizzi starts poisoning Cosimo's food through his prison guard. Contessina negotiates exile rather than the death penalty.

While the Medici are in exile in Venice, the situation deteriorates day by day in Florence, with Albizzi imposing his rule over a city gravely depleted by the absence of the Medici.

The return of the Medici to Florence is an out-and-out triumph, with Albizzi in prison for his attempt to become the city's "tyrant".

The Signoria now has a vacant chair, and Cosimo is asked to choose who should occupy it. Piero thinks that his moment has now come, but the banker Pazzi, too, has his eyes set on that seat.

Pazzi has managed to convince the Pope to remove the Medici as Church bankers, but Cosimo is disinclined to surrender what he has worked so hard to attain.

After a surprise attack, Lorenzo and Giuliano search for the culprits. The trail leads the brothers to the Pazzis, but treachery lies closer at hand.

Lorenzo's power play comes at a cost and stirs up outrage. With leadership comes sacrifice as he travels to Rome and weighs an advantageous match.

The death of the pope brings strategic challenges as Lorenzo negotiates with the Duke of Milan and welcomes his new bride, Clarice, to Florence.

Lorenzo aims to strengthen ties with the Pazzis and proposes a treaty with Venice. Clarice appeals to Lucrezia and learns the way to Lorenzo's heart.

In opposition to the pope, Lorenzo moves quickly to acquire the strategic city of Imola. A forbidden love flowers between Giuliano and Simonetta.

The papal army advances as important coalitions shift. Meanwhile, Lorenzo negotiates a crucial treaty, and Jacopo attempts a major power grab.

As forces threaten a fragile alliance, the Pazzis embark on a murderous plan to destroy the Medicis while Lorenzo seeks to make peace with Rome.

The day of reckoning arrives as the circle of conspirators tightens around the Medicis during Mass, and rivals attempt to take control of Florence.

The entry into the field of the Kingdom of Naples alongside the papal troops is likely to mark the end of Florence. Among the Priors there are those who doubt Lorenzo, but the Magnificent, determined not to let Florence fall into the hands of his enemies, finds a stratagem to deprive the Priors of authority. Lorenzo decides to leave for Naples to try to break the encirclement and restore peace.

Arriving in Naples with Bernardi, Lorenzo finds it difficult to convince King Ferrante of Aragon to abandon the alliance with the Pope. While the Magnificent tries to win the king's trust, Florence remains under siege: the people and Clarice herself fear that Lorenzo has abandoned them.

Seven years have passed and Lorenzo hopes to close the accounts with the Pope by obtaining the signing of a peace treaty between the various Italian rulers. Riario hopes to induce Lorenzo to return to open war. While the Magnificent faces this new diplomatic crisis, his mother Lucrezia involves Clarice in the management of the bank. Worn out by the constant clash with Sixtus IV, Lorenzo decides to start his son Giovanni on an ecclesiastical career hoping to increase the influence of the Medici in the Roman Curia. The Treaty of Bagnolo, signed by all the Italian rulers, marks the triumph of the Medici family and Lorenzo, who has become the deciding vote of Italian politics.

Sixtus IV is dead. Lorenzo and Clarice travel to Rome to support the election of their candidate for the papal throne, but they have to deal with the plots of Riario. The Medici find an unexpected ally in Caterina Sforza, Riario's wife. Despite the family's efforts, the new Pope Cybo proves difficult to control. In Florence, Savonarola harangues against Lorenzo for his influence in the conclave.

Lorenzo begins to show the first symptoms of a serious illness while his political enemies decide to attack him, questioning the solidity and provenance of Medici Bank's capital. Among these, Tommaso Peruzzi, once a supporter of the family, is now eager to bring to light a scandal that would condemn the Medici to exile. To cover up the crime and avoid losses, the Magnificent risks a new war and plans to kill Peruzzi.

Savonarola, who had taken Tommaso's confession, denounces his killing and openly accuses Lorenzo, who however continues to deny. Clarice begins to suspect the truth. To continue his strategy of control over the Holy See, the Magnificent makes a promise that triggers a family crisis.

Lorenzo allows Bernardi to convince him that the only solution not to lose everything is to kill Savonarola, whose following gets bigger and bigger. By now, the friar openly preaches the overthrow of the established order to found a new Jerusalem. Lorenzo's plan is ready and the assassins recruited ...