Based on real events during the unification of Spain.
Spain, led by Ferdinand the Second and Isabella of Castile, soared to the height of its power. The policy of the cunning king bore rich fruit. The whole country was taken away from the king of Portugal. By deceit the southern fiefdoms were cut off from France. The master of southern Europe and northern Africa he - King Ferdinand, or rather by his hands and the instruction of Isabella, brought out of slumber and made all-powerful "Manu interpida" - the Inquisition. And now this mechanism was bringing into the king's treasury, first one-third, and now more than two-thirds of all the confiscated goods. And henceforth no one, whether grandee, marquis, or prince, could feel safe. Forsaken, beware - they are coming for you!
Young Merinda, who did not wish to become Esteban Junior's mistress, was thrown into prison. Esteban the elder - the second man after the king - so wished. The sentence is ready, all that is left is to disfigure the maiden and then burn her at the stake. But something goes wrong. Fernando, an incorruptible knight of the Hospitaller Order, is in charge of the case. An obvious lie, not proof of guilt. All turn against Fernando the Inquisitor. Fernando has no choice but to save the girl at the cost of his career and even his life. He flees from pursuit along with Merinda. The couple is put on the wanted list. Whoever shelters or helps the fugitives will find himself behind bars. The new inquisitor hires an assassin to find and kill the fugitives without publicity.
The former favourite of the King of Spain, the Countess of Alba, writes a letter to his Highness and admits that she bore his daughter in secret. She asks the King for help in finding her daughter who has disappeared. The King entrusts his confidant, the Marquis Diego, with the task. The Marquis finds the trail - the King and Countess´ daughter is none other than Merinda!
The King dismisses the false accusation. But the Inquisition's Purgatory flywheel is unwound. Merinda and Fernando are driven into the mountains and their doom is certain. The pair stand on a precipice above a precipice. The crossbowmen have them in their sights. The Marquis gets there in time. He stops the execution.
He untwists the chain of false witnesses. This leads him to plot against the king. He writes a letter to the king and sends it with a messenger. On the way the messenger stops for a drink of water and water for his horse. He is killed by an assassin hired by the Inquisition. He reads the letter and sells it to the conspirators. He then sells the information to the Marquis that the conspirators have intercepted the letter.
The Marquis learns through his agents that Admiral Esteban and his goons have followed the trail of Merinda and Fernando and wish to kill them all.
The plot is averted. The King accepts a payoff from the repentant accomplices. It turns out the murderer is not dead from the poison, seeking a meeting with the Marquis for revenge. Such a moment arrives. The Marquis is stunned. A lung is punctured. Merinda dismisses the court physicians. She saves the Marquis´ life herself with the help of herbal infusions and extracts of mould. Merynda is slandered by the physicians as a sorceress. The Queen throws the young Countess into prison. The King himself is powerless against the Queen. Merinda´s death is imminent. But then, passing through the cheering crowd of the townspeople, the King is tried to be killed by his old hater. The wound seems trifling. But twenty-four hours later, the king is taken ill and falls into unconsciousness. The queen realises that the court physicians are powerless, and so are the prayers. She decides to enlist Merinda's help. Nothing is more important to the king's daughter than saving her father's life. Two weeks later, the king is back on his feet.
The queen is pleased with the king's recovery, but still wants to get rid of Merinda...