In episode 804 of 'La Promesa', María and Carlo argue about the house Manuel has offered them, creating a tense atmosphere. Cristóbal intervenes to calm the situation, while María experiences discomfort related to her pregnancy. Manuel and Julieta return from a business meeting with the Duke of Carril, where Julieta shows skepticism about the proposed investments. Martina receives an invitation to a ball, and Ángela and Curro have disagreements about the search for the noble title.

The distance between Pía and Ricardo grows, and Adriano arrives with the newspaper 'La voz sureña', where the chronicle about the refuge will be published, generating anticipation. In episode 805, Martina, Adriano, and Jacobo read the positive chronicle about the refuge, which generates jealousy in Jacobo. Curro argues again with Ángela about his noble title and decides to send the letter to the king without his father's signature. Pía and Samuel talk about the problems between María and Carlo, and Julieta shares Ciro's intention to invest his dowry in businesses proposed by the Duke of Carril. Ricardo explains to Pía the truth about the 'As de Copas', and Vera is about to meet her father. Finally, María decides to break up with Carlo.

In episode 806, Curro tries to prevent Vera from being discovered by her father, the Duke of Carril, who visits 'La Promesa'. María Fernández, after arguing with Carlo, publicly breaks up her relationship, stating that they will raise their son separately, with Petra, Simona, and Candela as witnesses. Alonso regrets and decides to support Curro in his claim for nobility, committing to sign the petition to the king. However, Ángela is pessimistic about the deadlines, generating a new conflict, although Leocadia supports Curro.

Martina receives praise for her interview about the refuge, but she is worried about the delay of the Patronato until, finally, the expected letter arrives. The plot unfolds in the context of 1917, with the threat of a general strike and the imminent arrival of the Spanish flu in 1918.

The story of 'La Promesa' focuses on the personal relationships and social aspirations of its characters. María Fernández's decision to be a single mother marks a turning point in the plot, while Curro struggles to obtain his noble title, facing obstacles and disagreements. The intrigues and secrets of the past continue to affect the present of the characters, creating an atmosphere of constant tension and drama.

The series explores themes such as love, ambition, loyalty, and family secrets, set in a historical context that adds complexity to the narrative. The characters must face personal and social challenges, making decisions that impact their lives and those around them.