In Maui, Agnes is furious and frightened after six days without a real explanation from Stafford. A technician is installing a new security system, which she had ordered after another recent break-in in their gated community. Feeling abandoned and unsafe, she decides to take a sleeping pill and go to bed, certain that Stafford won’t be home that night. She now keeps a handgun for protection.

The perspective shifts back to Stafford and the children as they deplane. The warm, humid air greets them, and the children seem tired but curious. Inside the airport, Stafford leaves the children to collect the luggage. The family is completely silent during the long drive from the airport to Stafford’s house.

Just after midnight, Stafford drives the children to his home, planning to sneak them into the guest suite without waking Agnes. As he drives, he reflects on his terror at his new responsibility and on Donny’s continued silence. His thoughts drift to his past, recalling how he fled to Los Angeles after the death of his son and stumbled into a successful but ruthless career as a television executive. He remembers climbing the studio ladder by being a shrewd “alchemist” who could identify hit shows, eventually becoming vice president of creative. His fall from grace came when a writer he disliked took his show to another network for eight award-winning seasons.

They arrive at the house, passing through the security gates. Stafford points out that their house is at the top of a hill with a water view, but it’s too dark for the children to see anything. The property is isolated and sometimes surrounded by the sounds of feral cats, which Stafford associates with death.

Agnes has nightmares about the day her mother, Evelyn, died. The narrative contrasts the fabricated story that Agnes would tell her whole life—that her mother was a virtuous war widow who died suddenly of a heart defect—with the grim reality that Stafford would later uncover through his own research. Stafford learned that Evelyn was an unwed teen mother and a sex worker who had an addiction. Agnes was placed in foster care after Evelyn set their apartment on fire. As a seven-year-old, Agnes ran away from foster care and was picked up by a strange man, who assaulted her in a park. After escaping her attacker, Agnes went to her mother’s apartment and found her dead. She took her mother’s change purse and bought an ice cream just as the police arrived, alerted by the smell of decay from the apartment. They discovered that Evelyn had been dead for three days. The authorities concluded that Agnes stole from the corpse, leading her to be labeled “emotionally disturbed” and sent to live with her grandmother.

A new security alarm awakens Agnes, who grabs her handgun. Unfamiliar with the weapon, she panics, accidentally firing it three times while moving through the house, once through a window, once into the ceiling, and once into the dishwasher. She injures her foot on broken glass in the process. She finds her husband at the side entrance, where he has just returned with four children and is trying to disable the alarm he triggered. Stafford, who appears disheveled, tells Agnes to put the gun down, but she drops it. As Andy reaches for the falling weapon, Donny catches the gun. It fires anyway, the bullet grazing the hem of Stafford’s pants before hitting the wall. Donny safely unloads the final round and advises Stafford on proper gun storage.

The morning after Stafford’s arrival with the children, he and Agnes sit by the pool. She reveals that she bought a gun and took Ambien because she was terrified after Stafford called from Napanee and then disappeared. In turn, Stafford confesses the full story of his youth: He betrayed his best friend, Bobby, by seducing his girlfriend, Carrie Ann, which led to Bobby freezing to death. He confirms that the children are Bobby’s grandchildren. Agnes then reveals her own past, explaining that she was a chambermaid at a motel across the border where she met college boys from Queen’s who invited her to Kingston for homecoming; she took the bus there and was humiliated because the boys saw her only as a sexual conquest, but she ultimately met Stafford. Stafford mentions that he was fired from his job as a TV executive. Confronted with these truths, they decide on a future together. Agnes rejects Stafford’s offer to DNA test the children to see whether they’re related to him or Bobby, stating that it no longer matters. They agree to raise the four children as their own, deciding to tell Callie that they’re now the Shepherds’ guardians.

Through a series of emails, Callie expresses her outrage upon learning that her parents are taking in the Shepherd children. Agnes acknowledges their past failings as parents and invites Callie to meet the children in Maui, but Callie initially refuses, citing a new relationship and a need for privacy. As Agnes plans and then cancels a trip to Los Angeles, Callie reveals that her new partner is a woman named Cynthia. Agnes responds with acceptance and support. After a successful phone call, Agnes emails a lengthy update describing how she and Stafford are embracing their new life, even as their friends ostracize them. Stafford is bonding with the boys by building them a bunkhouse. Agnes extends an open invitation for Callie and Cynthia to visit, marking a significant thaw in her and Callie’s relationship.

Stafford and Agnes work to create a new life in Hawaii for the children. Donny finds purpose in constructing a bunkhouse, a project that Stafford supports with patience and quiet encouragement. The children process their grief in different ways: Lucy has tantrums, Donny withdraws, and Andy becomes sad during happy moments when he misses his parents. Stafford worries most about Bobby, who stoically holds the family together. A fragile routine emerges as Stafford and Agnes hire tutors, arrange activities, and discuss their uncertain future. A turning point occurs during a family beach trip, where Andy’s questions prompt Stafford to begin sharing Shepherd family history, capturing both Andy’s and Bobby’s interest. Andy documents their new life with a Polaroid camera. The day culminates in a moment of normalcy, with the boys snorkeling and Stafford letting out a genuine, happy laugh. While observing the scene, Agnes feels a sense of hope, realizing that they might be forming a real family on the island.

The narrative moves forward to April 2, 2016. Writing a letter to his brother Donny from Maui, Bobby recounts the recent death of Stafford. He explains that he was there by chance after his spring-break plans fell through. Stafford developed a sore throat that became bronchitis and then pneumonia; the official cause of death was acute respiratory distress syndrome. He had refused to go to the hospital until Agnes and Cynthia intervened, but by then, it was too late. While Callie could have made it in time to say goodbye to her father, she did not.

Bobby describes Stafford’s final day, noting that he seemed resigned rather than afraid. After Stafford lost consciousness, Agnes demanded that the hospital staff remove all his tubes so that she could see his face. Agnes told Bobby that Stafford wanted him there, framing it as Stafford’s own wish. In what Bobby calls a “heroic” act, Agnes stepped back and let Lucy and Andy hold Stafford’s hands as he passed away. The letter concludes by informing Donny that Stafford wished for his ashes to be buried in Napanee and that the family will gather there soon for a memorial.

The Epilogue presents a brief scene in which Stafford and Bobby play together and then quietly lie on the ground to watch the sky.