Josie invites April out for dinner to give her a break from the household stress. Leo pointedly ignores the conversation, reinforcing the ongoing financial and emotional strain in their marriage. Despite feeling hesitant to leave her family, April agrees.

At a rooftop restaurant, Josie asks about April and Leo’s relationship. April keeps her answers vague, secretly dreading how furious Josie would be if she discovered that April had been unfaithful. The sisters then discuss their parents’ newly exposed shotgun marriage. While Josie focuses on their mother’s hypocrisy regarding abstinence, April finds comfort in the possibility that Deb might understand the consequences of a regrettable sexual encounter. However, April also worries that her parents’ enduring marriage sets a standard that she and Leo might fail to meet.

While Josie is in the restroom, a stranger approaches April and asks for her phone number. April rejects his advances by displaying her wedding ring. The man remains undeterred, noting her apparent sadness and continuing to flirt. Although April turns him away, she feels privately flattered and is disturbed by a creeping sense of dread that she might be single in the future. When Josie returns, she criticizes the stranger’s blatant disregard for marriage vows, prompting April to drink her wine in silent, lingering guilt.

The narrative flashes back to April’s 34th birthday, which Leo forgets entirely. She lies to her parents and says that he treated her well. She then discovers a friendly note to Leo from his coworker Kim. When her boss, Cody Blanchard, later returns with a belated, personalized gift, April—feeling seen after being ignored—encourages his advances. Leo walks in and discovers them together. April tells Cody not to contact her again and makes no effort to stop Leo from leaving, seeing the affair not as a plea for Leo’s love but as an admission that she has already lost it.

Back in the present, Leo plans to discuss the divorce with April, but she returns home drunk and confronts him. She insists that she and Cody never had sex; Leo retorts that marriage vows go beyond sex. Their argument breaks when Sadie reveals that she has lost her first tooth, shifting the mood to excitement. Later, Leo tells April that he wants a divorce that causes their children the least pain. The next morning, having forgotten to play “Tooth Fairy,” Leo finds Sadie devastated. April saves the moment by faking a text from the Tooth Fairy explaining a delay. The successful co-parenting pains Leo, who realizes that he still loves April but can’t trust her.

Deb sends Billy off to his final week at his dental practice. Cameron announces that he has accepted a job in Dallas. That evening, Billy gets lost walking home; Deb and Cameron find him nearby, disoriented and frustrated. Cameron installs a location-sharing app on Billy’s phone and posts reminder notes around the house. Overwhelmed by the prospect of managing repairs and Billy’s increasing needs alone, and recalling the doctor’s warning that Billy will become a “shell” of himself, Deb calls a repairman for the broken washing machine and begins to wonder whether their home is the right place to face what’s coming.

April and Leo arrive at their fire-damaged Argyle home just before a major storm and discover a squatter named Nathaniel inside. When a tornado siren sounds, all three shelter in a hallway while the storm rips the protective tarp from the roof. Leo reads aloud from The Little Prince to calm them. Afterward, Leo drives Nathaniel to a shelter and returns to show April a newly found photo of his father, also admitting that he once squatted himself, something April never knew. On the drive back to Dallas, April realizes that she has pitied Leo’s past rather than tried to understand it.

Cramped at his in-laws’ home and stressed by costly repair updates, Leo endures added tension when Josie plays his and April’s wedding song, forcing an awkward dance between them. Shortly after, a confused Billy mistakes Leo for his son and demands to know why he isn’t in an old family photo. Leo decides to rent a trailer on his Argyle property to gain distance from April. They gently inform Sadie, and April tells her family, who offer quiet support. A week later, Leo moves in; the solitude recalls his lonely childhood, and he ends the night searching for his parents’ names online.

At Otto’s first birthday party, Josie announces that she’s getting tested for the Alzheimer’s gene, creating immediate tension. Cameron is staunchly against knowing, April is undecided, and Rachel is visibly concerned about the implications for their future. Deb observes their diverging reactions and worries that the burden of care will fall entirely on April. While watching Billy sleep, she questions whether their family home is the right place for his long-term care and considers whether a specialized community would better support him and protect their children.

April is served divorce papers at her parents’ home and is angered that Leo cited “irreconcilable differences” rather than infidelity, feeling like the vague language erases their specific, mutual faults. Two days later, Josie’s genetic test comes back negative. While Billy is deeply relieved, April grows anxious about her own memory lapses and the possibility that she or Cameron could still carry the gene. Josie’s carefree response alienates her, and April is left imagining a future in which her family slowly forgets one another.

When Leo arrives to pick up his children, Sadie insists that April join them, and they spend the day at a park appearing to be a happy family. That evening, April drives to Leo’s trailer to return his phone; they share a drink and comfortable conversation until an old intimate gesture creates an awkward moment. After she leaves, Leo is struck by how much he misses her. She abruptly returns and confronts him, demanding to know why he gave up on their marriage before her affair. They argue fiercely. She accuses him of emotional absence long before he left, while he insists that she pushed him away. April storms off, leaving Leo alone with his anger.

Deb shows Billy information about Greenwood Hills, an assisted-living community, and is surprised by his openness. When they tour the facility two days later, Deb feels out of place, but Billy connects with a fellow resident who was also a dentist and seems content despite immediately forgetting a detail about the place. Back at home, Billy reveals a bottle of pills, asking Deb to administer them to end his life if the time comes—framing it as a way to spare her years of suffering. Deb tries to flush the pills, but Billy stops her, arguing that they should keep them as an option since circumstances and minds can change.

April drops the children off for their first overnight stay at Leo’s trailer, moved by the effort he has made to welcome them. At five o’clock in the morning, she wakes with a sudden realization that the hardware-store manager whom she and her father met in Waco bore a lion tattoo identical to the one in the photograph of Leo’s father. She drives to the store the next day and confirms that the manager is Ricardo “Rico” Torres, Leo’s father. She learns that he “lost” his family in Odessa years ago and notices a semicolon tattoo, a symbol that commonly suggests a past suicide attempt. This detail makes her see him as a more complex figure. Deciding that it’s not her place to reveal the truth, she leaves. On the drive home, humbled by how she previously viewed Leo’s past, she receives his call telling her that their insurance company has declared their house a total loss.