The Bedouin chief presents to the children the second veil they were looking for, transmitted from generation to generation by the Chaldis tribe. They try to read a plan to the city of gold, but the sails do not reveal anything.

In the desert, the suspected noises heard are produced by none other than Sancho and Pedro lost in the dunes. They finally found their friend Mendoza. In Manfuha, the children try to leave the oasis to reach the Condor, but the compass they steal from Zarès detects something.

The Olmecs place the Sun Power Unit at the bottom of their sunlight collecting crystal and activate it. However, the unit does not behave as expected and the Sun Power Unit begins to overheat. The High Priest of the Cities of Gold, who turns out to be Esteban's father, tries to shut it down using Tao's jar which is actually a control unit. But he could be too late.

Back in the village, the children happily reunite with Ambrosius. Mendoza reveals to Esteban that his father is alive and waiting for him. Esteban meets with his father, but their reunion is cut short.

On board the nave, Laguerra prevented Gaspard from killing Mendoza, arguing that Mendoza would be more useful to their living plan than dead. The children enter the city in search of the tomb of Princess Rana'Ori, but the sumptuous city seems deserted.

Inside the first City of Gold, Esteban finds a great Golden Condor. When the volcano on which the Cities are built begins to erupt, the Cities are destroyed. Sheltering inside the body of the Condor, they try to make its mechanism work, using the Medallion of the Sun. Suddenly, the giant bird spreads its wings and takes flight.

After Arabia, our heroes set course for Africa. In pursuit of Ambrosius, the climb Lalibela, in Ethiopia. There, Esteban and Tao explore a church whose walls are covered with religious murals. To their shock, one of them depicts the pyramid of Mu being carries in a procession! But the church hides something else: a strange machine from Mu. Convinced this machine will provide them with a clue leading to the next city of gold, Tao is hesitant to leave, against the advice of Esteban who suspects a trap laid by Ambrosius. Rightly so...

With Tao as a hostage, the Olmecs force Esteban and Zia to use their medallions to open the doors to the City of Gold.

In the Indian Village of the New Sun, Zia at last finds her father, Papacamayo. But her happiness is short-lived, when he dies from his wounds, after defending the village against an attack by the Olmecs. All the Mayan tribes unite to fight against the Olmecs.

The setting sunlight leads Esteban and his friends to the statue of the earth goddess, Pachamama. The legend goes that when Pachamama takes the sun in her arms, the Gates to the Cities of Gold will open. Estaban and Zia place their medallions in the statue and the mountain opens up to reveal the first City of Gold. Inside they discover a great bird, made of solid gold.

The children reach Condor thanks to Laguerra who confronts the soldiers alone at the risk of his life. Despite the reluctance of Tao, our heroes return to collect it and make it climb aboard. Under the fire of the defensive guns of the fort, they managed with the Condor to recover the box containing the sails.

Our young heroes and Ambrosius have managed to enter the second City of Gold. Esteban and Zia receive a message delivered by holograms of The Sages of Mu and Atlantis.

Searching for the Cities of Gold, Esteban and his friends cross a high plateau up in the Andes. Near Lake Titicaca, they are attacked by the Urubus, a tribe of giants. Tao invents a submarine, and they capture Karuga, chief of the tribe, and hold him prisoner. Karuga tells them that there's a City of Gold on a mountain, guarded by the earth goddess, Pachamama.

The Mayan people arm themselves and attack the Olmecs, who have been tyrannising them for years. A fierce battle takes place near the entrance to the Olmec base. From the Golden Condor, Esteban and the other children bombard the Olmecs with stones, turning the tide of the battle in favour of the Mayas.

The great Golden Condor, carrying Esteban and his friends away from Pachamama and the erupting volcano, lands in the desert at Nazca. But when Pizarro and his soldiers arrive, Esteban makes sure everyone escapes.

Esteban flies the Golden Condor against the terrible Olmec war machine, to try to rescue Zia. Tao and Esteban manage to leap onto the machine in mid-air, and Zia is saved. But Tao is left behind, a prisoner.

In the jungle, Esteban and his friends discover some ruins, deserted temples and pyramids. In one of the temples, Pedro and Sancho try to remove a jade mask from the wall when the mask begins to glow. Suddenly the stone beams shoot out of the walls, ceiling and floor and trip them up.

Our heroes have escaped The City as it was closing in upon itself. So has Ambrosius, who has stolen a matrix of olishark from the City of Gold.

The Golden Condor carries Esteban and his companions to the High Peak, where they encounter the Spanish forces, armed with their cannon. With the help of the Golden Condor, they stop Gomez and Gaspard. And when they had saved their friends, they leave the High Peak, in search of the land of the Mayas.

After solving the secret of the green jade mask, Esteban and his friends find a manuscript which seems to hold the key to the whereabouts of the Cities of Gold. But almost immediately, they are captured by Doctor Fernando Laguerra and his friend, Marinche, who are also searching for the Cities of Gold. However, Kokapetl manages to rescue them all.

After wounding the High Priest of the Cities of Gold, Kalmec steals the Great Treasure, a concentrated source of the sun's power also called the Sun Power Unit. However, the security systems of the City are activated and destroy the Olmecs' flying machine. Kalmec and Menator make their way back to their base, taking the Great Treasure with them.

After much travelling and many adventures, Esteban and his friends finally discover the third temple built deep inside an enormous cave. A golden statue is holding a third manuscript which mentions a mountain known as "The Burning Shield".

Thanks to Yu Chunhe, the high priest of the Taoist temple, our heroes find the famous Yellow Dragon. Unfortunately, a man who has been spying on them since their arrival, steals the precious Dragon.

Esteban and his friends are captured by Indians who wanted to sacrifice them to purify their sacred lake of gold. Marinche and Doctor Laguerra try to poison the lake so they could get at all the treasure on the bottom. Mendoza foils their plan by breaking through the dam, flooding the village and allowing the children to escape.

Our heroes discover that the monk, Tian Li, is able to decipher ancient Chinese similar to that on Ambrosius' book. Tao and Esteban set off to go get the precious text in The Condor.

The two children, Esteban and Zia, find out that they both wear the same strange medallion. The Esperanza crosses the Atlantic and nears the entrance of the Straits of Magellan, where wild seas and strong winds create terrible storms. Mendoza, the navigator, prepares to spend four days and nights at the wheel.

Gomez and his soldiers attack the Fort of the Black Eagle to try to recapture the cannon Mendoza had stolen. Mendoza uses the cannon to fight back, but cannot stop the Spanish army who storm the fort and drive the Incas out. Esteban, Tao and Zia run away towards the High Peak, following secret underground passages constructed by the Incas.

Gomez' Spanish galleon overtakes and attacks the Solaris, the sun-powered ship on which the children are travelling. They manage to outrun the Spanish ship when Tao discovers a wonderful secret solar power boost, just in time. At last, they reach the new continent.

Gomez captures the children and forces Zia to reveal the secret of the Golden Quipu. It is an Inca message which reveals that the Cities of Gold lie beyond the High Mountain Peak. In the night, Esteban and the children escape. They find a secret underground passage and set off for the High Peak.

Having found the Burning Shield, Esteban and his friends fall into the hands of the mysterious Olmecs, who possess very advanced technology. They escape from them, but are captured again. So what will happen to them now?

In the center of the cave, at the top of a pyramid, our heroes discover a sphere of orichalque floating on a lake. Attacked by thousands of giant crabs, they manage to take refuge inside.

On the way to Peking, our heroes find refuge in a Shaolin temple. Mendoza, hurt during a fight, is taken care of by the Great Master. At nightfall, someone sneaks in to leave a venomous snake.

Mendoza narrowly escapes the attack of Ambrosius. The latter claims that it was Mendoza who assaulted him, but he loses his compass, which Esteban picks up and tends to him by reflex.

At the fort of Pattala, Esteban was spotted by Ambrosius. When escaping, he sees his father in a cell but must flee because he is persecuted by Laguerra, the right arm of Ambrosius, and the guards of the palace.

On board the condor, Esteban is worried about what happened to Mendoza and his men, but his friends remind him that Mendoza is resourceful and their priority is to prevent Ambrosius from appropriating the muen knowledge and make it Weapons of war like the black suns.

In the treasure chamber of the Golden City, the crowns found by our heroes allow the wearer to control the orichalc cubes by thought. As he goes to look for Tao in the Thallios to show him their discovery, Estéban passes by the statue: he seizes the crystal pearl.

Tao is now in the hands of Ambrosius. The latter tries to return to his good graces, but Tao sees him as a traitor and refuses to give him his confidence. However, Tao discovers the laboratory of Ambrosius and is impressed by all that it reveals to him.

The fifth city of gold is swallowed up as our heroes confront Ambrosius for the Stone of Ophir. A great maelstrom consumes the city and all are swept away. Carried by the flood, they are strewn here and there, all over the banks of the river. While Esteban helps the Olmec Tyrias, Zia is forced to rescue the Eternity Stone from the grip of Ambrosius. Alas, in vain...

Our heroes try to escape the pirates but Esteban and Tao are captured and taken to the pirate camp.

Our heroes are surrounded by a troop of Bedouins. Their intrigued chief observed the medallion and then returned it to Zia apologizing for the young thief: a Bedouin never flies. When the children leave, he asks the young boy to follow them to find out what they are doing in Ormuz.

After leaving China under the threat of Zares, our heroes finally arrive in Japan. They must absolutely find there the third City of Gold against which the infamous Zarès promises to release Athanaos, the father of Esteban.

The pirates attack Ambrosius' ship that transforms itself into an incredible flying Nave!

Mendoza and his men takes control of the nave and makes the prisoners Gaspard and Ambrosius. They spot the Condor and rediscover the children who introduce Yoshi and his family.

Zarès managed to escape with the crown and the crystal pearl. Aboard the Condor, Esteban explains his plan to his friends. He arranged for Zarès to take the crystal pearl that had guided the Thallios to the golden city.

The mysterious pursuers turn out to be children whose parents were abducted by the men of Ambrosius to work forcibly at the Fort of Pattala. When they learn that our heroes are not friends of Ambrosius and that Esteban's father is also a prisoner, they decide to unite their strength to deliver them all.

The fort is taken by assault from all sides: the villagers, Tao and Atanaos are freed. Esteban manages to inject the antidote to the Raja who regains his spirits and realizes the betrayal of Ambrosius. To escape the soldiers of the Rajah, Ambrosius uses the black suns that trigger a fire in the fort.

Inside the temple, the shield-mirror leaves the children perplexed: according to the silhouette in the utsuro bune, it is the path and the key to the next golden city. They realize then that the ornaments of the mirror represent a volcano, off Kagoshima. Will the city be underneath?

At night, as Ichiro goes to take his guard duty at the castle, Esteban follows him and tries to convince him to help him to escape Mendoza and his men. Ichiro refuses, reminding Esteban how his presence and those of his friends already endangers his whole family.

According to the plans of Ambrosius, Laguerra and the soldiers find only a deserted village. Laguerra spotted the children hidden in the trees. She hesitates, but does not denounce them and leaves without saying anything with her men in direction of the fort.

Esteban spends his own time with his father Athanaos finally found. This one reveals to him well to know Ambrosius, to have been his friend when they were young. For their part, Zia and Tao discover in the Memory Temple a key clue in the search for the fourth golden city.

While searching for The Eyes That See All in the ruins of a cursed temple, our heroes are attacked by Zares who lashes out on Mendoza, Sancho, and Pedro.

Chasing a young boy, who has kidnapped Pichu, back to his village, Esteban and Zia find Mendoza and the sailors safe and sound. Meanwhile, Ambrosius heads for the Olmec base to repair his ship, sabotaged by Magon.

After Ambrosius's disappearance, Laguerra and Gaspard are almost killed in the volcanic fault. They manage to escape but the heavily damaged flying ship crashes shortly thereafter. Meanwhile out heroes follow the path of the Bako to the mythical city of Orunigi where, according to the legend, the sacred mask was made.

The Leopard-men set fire to the village to create a distraction enabling them to kidnap Zia along with the sacred mask. Out heroes learn that she is being held by the powerful sorceror N'Deye, in the city of Tellem, abandoned for centuries at the foot of the Bandiagara escarpment. Jealous of the link between Zia and the Bako, the sorceror tries to force her secret from her. But, faced with his prisoner's silence, N'Deye has her taken to one of the caves in the Cliff of Spirits. While at the top of the cliff, Esteban and Tao attempt to climb down and save their friend, Zia explores the caves to try to find another exit.

While pursuing the man who stole the Yellow Dragon, Esteban finds himself stuck inside the Forbidden City and must pass himself off as the Imperial Prince!

The one who attacks Esteban, Tao and Zia is Yoshi, an old man who keeps fiercely the impressive Orichalcum sphere. Yoshi reveals to the children that it is a utsuro bune, a sacred object, rejected by the sea thousands of years ago and revered since as a gift of the gods.

While in the village, the children try to repair the Condor, Pichu sent by Tao finds them and deliver them a message from Atanaos. He reveals that the Rajah was drugged by Ambrosius.

The children finally managed to penetrate inside the ziggurat. They start their descent in search of the sacred sails of Princess Rana'Ori in the bowels of the pyramid, where, according to the inscription discovered in India, they should be found.

In the Lenje village, Zia, Tao and young Temba are welcomed with great fanfare. Impressed by Zia and her link to the sacred mask, the matriarch confirms that she is the one who must take the Bako back to the place where it was made, the mythical city of Orunigi.

Esteban and Tao find Zia in the caves of the Cliff of Spirits where the sorcerer N'Deye has imprisoned her. Together, our heroes explore the depths of the cliff and find a secret gallery where the statues grouped around Princess Rana'Ori reveal to them the location of the sixth city of gold. Meanwhile, Mendoza, Pedro and Sancho attack the sorceror and his Leopard-men to retrieve the precious Bako. Reunited once again, Esteban and his companions set out for the city of gold. But while using the sacred mask again, Zia unleashes a terrible storm...

Caught in a lightning storm, the Golden Condor crashes into the impenetrable forest of the Congo. There, our heroes are met by the guardians of this place, gorillas who escort them to the heart of their kingdom, next to a seemingly bottomless chasm. The Bako then guides Esteban, Zia and Tao to its home: Orunigi, the sixth city of gold, which to the children's great joy, opens to them. At the peak of this incredible tree-city, they find princess Rana'Ori who finally reveals to them the true goal of their mission: use the great heritage of Mu and Atlantis to prevent a great cataclysm which could destroy humanity!

After a dangerous journey, Esteban and his friends are washed up on a mysterious island. That night, a shadowy figure comes creeping towards them. Silently, the figure steals a chart and a pistol, then snatches up Zia. Esteban gives chase. He discovers a curious house in a tree, where Zia is a prisoner. To Esteban's surprise, the mysterious shadow turns out to be a friendly boy of his own age, called Tao.

Esteban has disappeared the morning after Mendoza told him the truth about his father. Thanks to Pichu, his friends follow his traces to find him.

Hiding in the Imperial Palace, Esteban finally manages to recover the Yellow Dragon. Tao and Ambrosius concoct a Plan B to help him escape from the Forbidden City.