At the age of 12, Esteban, a foundling from Barcelona, possesses a unique power to summon the Sun and is referred to as the "Child of the Sun." Upon the passing of his adoptive father, he discovers that he was saved from a sinking ship as a baby. His mysterious medallion has a connection to the New World, where the enigmatic Cities of Gold may be located. Eager to uncover his true identity and locate his birth parents, Esteban embarks on a journey to search for them. Along the way, he encounters a young Inca named Zia, who was abducted from her tribe years prior and bears a similar medallion. Later, they meet Tao, the last descendant of the Heva Empire and a Robinson Crusoe of the Galapagos. The three children set out on an adventure to find the Cities of Gold by following the shining star, Coyolite, depicted on their medallions, hoping that it will lead them closer to their missing families.