Beatriz (Sylvia Pasquel) and her elderly husband, El Viejo (Alejandro Suárez), live trapped in a toxic, claustrophobic marriage defined by resentment, emotional abuse, and obsessive jealousy. El Viejo routinely belittles Beatriz, obsessing over her past and accusing her of lingering sexual desire and infidelity. To humiliate her further, he carries on an open affair with their housekeeper, Isabel (Patricia Reyes Spíndola), while forcing Beatriz into total submission. Absorbing his abuse, Beatriz eventually internalizes the degradation as a perverse form of validation. She seeks out tango lessons with a younger dance instructor (Daniel Giménez Cacho), leading to an extramarital physical encounter that blurs the boundaries of revenge, self-assertion, and marital toxicity.