Anna is involved in an affair with her husband's older brother, harboring desires that can no longer be satisfied by sex with her husband alone. While concealing her illicit relationship with her brother-in-law, she repeatedly gives in to passion, eventually engaging in bold affairs with him right in the living room while her husband is asleep. Seizing the opportunity when her husband is unconscious, she continues their trysts, sinking deeper and deeper into this forbidden relationship with her brother-in-law.