La otra alcoba

Marcos, a wealthy Madrid businessman, is married to Diana. Their life appears luxurious, but they remain childless after years of trying. Diana's hope for a child clashes with Marcos's hidden sterility, and she considers adoption as a possible solution.

Marcos reveals his sterility to Diana, admitting he has hidden this for years. Diana responds by noting that she already knew something was off, having consulted a gynecologist who told her she could conceive. The revelation intensifies her resolve to have a biological child.

Diana's longing for a child drives her toward Juan, a gas-station attendant with modest means. A car oil leak leads to his helpful intervention, sparking a strong mutual attraction. Juan and his girlfriend Charo are engaged in their own plans for a better life.

While Marcos is away on a business trip, Eduardo invites Diana to a nightclub where she unexpectedly encounters Juan and Charo. That night Diana has an erotic dream about Juan, foreshadowing a dangerous romance. The encounter makes the affair feel suddenly possible.

Diana and Juan begin an ongoing affair, drawn together by desire and the secret of their different worlds. Juan opens up about his life while Diana keeps her own life private. Their relationship quickly becomes intense and consuming.

Marcos takes time off with Diana to ski in the mountains, offering a chance to salvage their marriage. On returning, Diana can't stop thinking about Juan and their affair resumes in secrecy. The growing divide between social classes adds tension to their relationship.

Baena, Marcos's friend with a mistress of his own, coincides with Diana and Juan in the same hotel where their trysts occur. He informs Charo that her boyfriend is having an affair, triggering a confrontation that tests loyalties. The revelation broadens the web of deceit surrounding the couples.

Diana discovers she is pregnant and grapples with her long-held desire fulfilled. She confesses to Juan that the baby is his and that she is still married, but she ends their relationship to protect her marriage. Juan is heartbroken and furious.

Diana tells Marcos the truth and he fears scandal more than love. He coldly arranges an encounter with his wife's former lover and offers Juan money if he stays silent. Juan refuses, leading to a brutal fistfight between the two men.

Diana's pregnancy ends in a miscarriage, plunging her into grief. The news forces her to confront the consequences of the affair. Meanwhile, Juan reconciles with Charo and they rekindle wedding plans.

Juan is beaten by men sent by Marcos to make him forget the past, a physical reminder of the consequences of crossing the social boundary. He endures the beating but remains resolute. Diana's world remains unsettled.

Diana recovers from her depression and sets her sights on a new man, a young athlete who recently won a swimming contest. She appears renewed and determined. Marcos, watching from a distance, seems to approve of this new pursuit.