Luzia is a 20-year-old orphaned kitchen scullion living a life of drudgery in Madrid. She secretly possesses Jewish heritage and magic abilities. She manipulates objects by singing small songs called refranes. She harbors a deep desire to escape her invisibility and improve her station in life. Her ambition drives her to demonstrate her talents, catching the attention of powerful figures holding a dangerous tournament.

Santángel is an immortal servant and assassin known as the Scorpion. Bound by an ancient magic spell, he must serve the De Paredes family or suffer physical destruction. He cannot age, though he experiences physical pain and intense emotions like rage. He possesses extensive esoteric knowledge and serves as Luzia's coach to prepare her for the upcoming tournament.

Hualit is Luzia's aunt and a Jewish woman practicing her faith in secret. To secure her safety and material comfort, she poses as a Christian widow named Señora Catalina de Castro de Oro. She corresponds with members of the Jewish diaspora. These letters provide the magical words used in Luzia's spells.

Valentina is the mistress of the Casa Ordoño and Luzia's employer. She feels lonely and overlooked in her loveless marriage. She seeks attention and social elevation in Madrid's high society. When she discovers Luzia's supernatural abilities, she pressures her servant into performing parlor tricks to impress influential guests.

Víctor is a wealthy hidalgo known as the luckiest man in Madrid. He enjoys immense privilege and uses his wealth to exploit others for his personal gain. He aims to elevate his status further by sponsoring a miracle worker in a secret royal tournament.

Fortún, known as the Prince of Olives, is a competitor in the secret tournament to find a holy champion. He presents himself as a humble country farmer who seeks a simple life. He creates magical illusions and plays music to impress the judges.

Teoda is a tournament competitor referred to as the Holy Child. She claims to receive visions and speak directly with angels. Her presence at the tournament commands reverence due to the Catholic faith's respect for divine miracles.

Marius is Valentina's husband and the master of Casa Ordoño. He is a native of Madrid who regards foreigners with hostility. He maintains a distant relationship with his wife and concerns himself primarily with the family's financial standing.

Antonio Pérez is the disgraced former royal secretary to King Philip. He hopes to regain royal favor after the failure of the Spanish Armada. He organizes a secret tournament at his palace to find a miracle worker for the king.

Gracia is a competitor in Antonio Pérez's secret tournament. She relies on illusions and physical attractiveness to impress the judges. She uses the competition as a venue to secure a wealthy husband.

Águeda is the cook at the Ordoño household. She distrusts Luzia's unexplainable abilities. She holds deeply superstitious views about the source of such miracles and protects her kitchen domain fiercely.

Quiteria is a playwright attending the events at La Casilla. She operates outside traditional expectations for women in Spanish society. She pursues her creative interests independently and forms a connection with Valentina.

King Philip is the ruler of Spain. He seeks a way to rebuild his empire's glory following the defeat of the Spanish Armada. His demands for religious orthodoxy and national power drive the actions of his ambitious courtiers.