The narrative begins with a mother and daughter riding in a taxi to the train station, where the mother will depart after visiting her married daughter, Catherine, and her family. Catherine feels relieved that the tensions from the visit will soon be over. She nearly laughed when her husband seemed uncomfortable as her mother offered a broad, insincere apology for her remarks, which mostly targeted their ‘‘thin and highly strung’’ son. Tony, battling a cold, opted to cough rather than engage with his mother-in-law. During the taxi ride, both women sense there's something unsaid between them. They ask each other if they've forgotten anything but stick to the safer topic of discussing the child. Their calm is briefly disrupted when the taxi driver suddenly brakes, causing the women to momentarily collide. They quickly rearrange their luggage to avoid any sense of "physical intimacy long since forgotten." Catherine had a closer bond with her father and is eager to distance herself from her mother. Only when the train starts moving do they call out to each other, "Mother" and "Catherine." Seeing her mother's shaky hand adjust the hat bought at Catherine's milliner's shop, Catherine suddenly wants to ask if her mother had a happy marriage with her father.

Having never formed the connections both women desired and feared, they part ways. Catherine resumes her usual brisk pace, relieved not to have to slow down for her aging mother. She feels beautiful and focuses on "the things of the world." After answering her husband's curt question, "Has she gone?" with a yes, Catherine heads directly to her son. The child, a distant and preoccupied four-year-old, is playing with a wet towel. She feels an unexpected urge to ‘‘fasten the child forever to this moment.'' As she hangs up the towel, the child calls her "Mummy" in a way he hasn't before, without any request following. Not knowing why, Catherine cherishes the moment and bursts into a wheezing laugh, which the child quickly labels as "ugly." Now more determined than ever to connect with him, she quickly gathers him up and takes him to the elevator, telling her surprised husband they are going for a walk. Tony, still coughing and blowing his nose from his cold, doesn't have time to react or stop them, even though he feels excluded.

From the apartment window, Tony observes the pair below, appearing "flattened" and lacking their usual perspective. The sea breeze tousles the child's hair. A sudden fear grips Tony, worried his wife might pass something—at first, he's unsure what—to their son. "Catherine, this child is still innocent," crosses his mind. He realizes it's a sense of imprisonment she might impart, one she would impose with a "morose pleasure." He envisions the child standing at the same window, feeling trapped, "obliged to respond to a dead man." Tony feels isolated in the efficient apartment his engineering job has secured for them. His family has formed a bond excluding him. He understands that beneath her calm demeanor, Catherine harbors resentment towards him and their achievements, both as a family and financially. Yet, he knows he is destined to sustain both. He sees their irritable child as detached from the safe life he and Catherine have created; the child embodies the irritation and frustration they both refuse to openly express.

As Tony's thoughts drift to dinner and the return of routine, he decides to visit the cinema afterward, to pass the time until nightfall, when "this day would break up like the waves on the rocks of Arpoador." He barely acknowledges the annoying sound of the elevator ascending, carrying his family. The noise or the idea that it "never stops, even for a second" seems to remind him of his lack of control over his family's inevitable march toward perpetual confinement.