Joy meets Elizabeth in the parking lot of the hospital in Newburgh, just across the Hudson River from Beacon, to return a calculator Finn left after her house. She observes Elizabeth’s exhaustion and the messy state of her car, reflecting on their sometimes-strained relationship. They discuss Hazel’s declining health, and Elizabeth surprises Joy by proposing that the three of them visit Hazel in two weeks. Elated, Joy immediately calls Hazel to confirm the plan. On the drive home, inspired by Hazel’s adventurous spirit, Joy acts on a rebellious impulse. With Hazel cheering her on over the phone, Joy speeds for the first time in her life, driving 15 miles over the speed limit and feeling an exhilarating rush.

In a flashback to 1993, Joy picks up her 20-year-old daughter from the train station. Elizabeth has spent spring break with Hazel in Brooklyn, and Joy is taken aback by Elizabeth’s transformation; she has peroxide blond hair and is wearing a colorful dress, a style clearly influenced by Hazel. Elizabeth excitedly recounts her trip, which included attending an abortion rights protest. She also reveals that, after talking with Hazel, she is considering breaking up with her steady boyfriend, Jack, in search of more romantic excitement. Joy feels a private sense of unease about Hazel’s “wild” influence on her daughter and advises Elizabeth to hide the protest from her conservative father.

The story moves back to the present. Worried about her finances and a new clanking noise in her car that she can’t afford to fix, Joy asks Rowan for help. He diagnoses the problem as a broken alternator bracket and offers to repair it, accepting only baked goods as payment. Joy invites him in for coffee, and they discuss Hazel’s illness. Joy expresses her frustration with feeling helpless, and Rowan shares his own experience of caring for his dying mother. He advises Joy to respect Hazel’s wishes and to treat her as the person she has always been, not as someone she is about to lose. He also suggests that Joy write Hazel a letter expressing her feelings, giving Hazel a way to feel Joy’s presence even when they are apart.

During a visit to Hazel’s loft, Joy notices that Hazel’s hair roots are growing in white, a clear sign of her declining health. Following Rowan’s advice, Joy tries to act normally and suggests a trip to the Brooklyn Museum. Hazel is enthusiastic but is suddenly overcome with nausea and becomes violently ill. They abandon their plans, and Hazel asks Joy to lie down on the bed with her. In an intimate conversation, Hazel admits she feels “inconvenienced” by dying and reflects that her unattached lifestyle has left her with few deep connections besides Joy. She also reveals she has hired a death doula, which makes Joy feel slightly replaced. After Hazel falls asleep, a dejected Joy returns to Beacon, where she is surprised and comforted to find Finn waiting at the train station to meet her.

A flashback to 1998 recounts Joy’s friendship with Percy Strahan, a kind Scottish widower she met while volunteering at a park. They developed a deep and easy companionship, and Joy found herself happier with him than she had ever been with Thom. One day, Percy confessed his romantic feelings for her, stating they made a “good pair.” Joy realized she felt the same way, but her sense of marital duty led her to end their friendship immediately. Ten years later, after reading Percy’s obituary, Joy received a note from his estate saying that he had never stopped loving her. Joy understood then what it truly felt like to have her heart broken.

The narrative returns to the present. Joy reluctantly attends a crafting circle hosted by Celeste, at the insistence of Rita. She feels immediately out of place among Celeste’s wealthy, sophisticated friends, who are named Bridget, Phyllis, and Maude, have had impressive careers, and look down on Joy’s simple lifestyle. Celeste’s attempt to act like they are lifelong friends irritates Joy. The catty conversation and judgmental atmosphere make Joy feel inadequate and acutely aware of how much she will miss her genuine connection with Hazel.

Rowan invites Joy for an afternoon at the Dia Beacon art museum. There, he tells her about his appreciation for art, a passion he developed while incarcerated at Sing Sing. Trusting him, Joy confesses that she was the one who pulled the library fire alarm. Amused, Rowan reveals his own secret: He and Philippe run a side business in which Philippe produces art forgeries, and they swap fakes into wealthy homes and sell the originals to one main private client, a collector who keeps everything in a temperature-controlled room in her Chelsea townhouse and truly cherishes what she acquires. He justifies his crimes as a way of redistributing art to those who will cherish it. Joy is fascinated, and their bond deepens.

Joy visits Hazel to give her a “spa day” at home. She pampers her friend with a manicure and pedicure and carefully dyes her hair to cover the white roots. Afterward, Hazel falls asleep, and Joy takes a walk through the Brooklyn neighborhood. As she passes several antique shops, she thinks about Rowan and Philippe’s forgery operation. A plan begins to form in her mind for a final, grand gesture to show Hazel how much she means to her.

While Finn works on a school assignment about the human capacity for both good and evil, Joy reflects on her own recent rebellious acts. Later, she goes to the pharmacy to conduct a “premeditated experiment” in theft. She successfully shoplifts a bottle of nail polish and then, growing bolder, puts on a bright blue sun visor and wears it out of the store. Both the employee at the counter and a police officer she encounters outside notice her headwear but make no comment. Having gotten away with shoplifting, Joy feels a deep satisfaction and concludes she is ready to proceed with her plan for Hazel.

Using a basket of garden vegetables as a pretext, Joy goes to Rowan’s house with an ulterior motive. Once inside, she tells him her plan: She wants his and Philippe’s help to create a replica of a specific vase so she can swap it for the real one herself. She explains the vase has immense sentimental value, as it was made by one of Hazel’s former lovers who died young. Joy insists on performing the riskiest part, swapping the vases, herself. Rowan is hesitant, warning her of the seriousness of the crime. To prove her nerve, Joy confesses to shoplifting the visor from the pharmacy. Moved by her emotional appeal and her desire to help her dying friend, Rowan says he will consider her request but makes no promises.

In a flashback to 2011, Joy is at the hospital with Elizabeth and a four-year-old Finn just after Thom has died following a ruptured brain aneurysm and three days on life support. Joy is shattered and overwhelmed, realizing she has no idea how to manage her life without him. She has no concept of their finances and feels she has no identity of her own. In the midst of her crisis, Hazel arrives, having flown directly from Egypt. Hazel comforts the family and promises Joy she will stay as long as needed, assuring her she will teach her all the practical skills necessary to be independent. As Joy cries, Hazel vows to walk beside her through her grief.

The story returns to the present. Joy, Elizabeth, and Finn drive to Brooklyn to visit Hazel. Because Elizabeth is exhausted from work, she asks Joy to drive on the freeway, something Joy has never done. Though initially terrified, Joy gains confidence and even speeds to pass a slow car, which impresses Finn. During the drive, Elizabeth confronts Joy about a rumor she heard from Rita that Joy is spending time with a “convicted felon.” Joy defends Rowan, downplaying his past and portraying him as a kind man. Elizabeth remains skeptical, and Joy reflects that lying is much harder to do with the people she loves most.