In 1298 the Genoese fleet attacks the Venetian ships. Marco Polo is captured and ends up in prison, where he starts dictating his memoirs to Rustichello da Pisa...

Niccolò and Matteo Polo, Marco's father and uncle, return from Venice as ambassadors of the Great Khan, and then leave for Cathay (China), this time together with Marco. The three arrive in the Holy Land, where Tebaldo Visconti tasks them with spreading the Christian gospel: in the Armenian deserts, however, they are attacked by Saracens...

After the Saracen leader has granted freedom to the Polos, the caravan can resume its journey and continue advancing into endless Persia. The Polos arrive in Hormuz, in the Persian Gulf, from where they intend to sail to China. However, the city was decimated by the plague and the ships were set on fire to stem the contagion. The Polos are forced to retreat towards the North.

On the Pamir plateau the Polos are swept away by an avalanche. Marco wakes up in the Muztag-Ata monastery, surrounded by golden Buddhas. After Niccolò and Matteo end up safe, the caravan crosses the Gobi Desert and reaches Shangtu, the capital of Kublai Khan's empire.

Prince Chinkin, during an imperial hunting trip, is struck by an epileptic seizure: Marco Polo helps him, but risks being executed, since the disease is a disgrace that no one must know about. Meanwhile, the court has returned to Cambaluc and the Mongol general Bayan, who led Kublai Khan's army against the Chinese Song dynasty, announces victory over Southern China.

The prime minister of the Great Khan Achmet is skeptical about the friendship between the prince and Marco Polo and decides to send the latter away by sending him to Southern China. There Marco meets Yang Ku, the poet, and is invited into his house: here he meets his daughter Mei Li and Monica, the orphan of a Dalmatian merchant.

In 1281's Khanbaligh, capital of the empire, the Chinese are plotting against the Mongols. The Great Khan's minister, Achmet, is killed and the revolt begins, culminating in the killing of the rebels. Meanwhile, Marco Polo has made a career...

Prince Chinkin dies and the loss deeply saddens Kublai Khan, who, upon hearing the news of Nayan's rebellion, does not hesitate to lead the army to subdue it. For the Polos the time comes to leave again to accompany Princess Kokacin to Persia to see her future husband.