The night Jack meets Rebecca, he has only nine dollars. As Franco Harris completes the Immaculate Reception, Jack takes Rebecca to a carnival. After it rains, he admits he could not afford an umbrella and that his life has been unstable since coming home from serving in Vietnam. Rebecca recounts their incompatibilities and the date's shortcomings but, because of "the way he looks at her," she kisses him and agrees to another date. Jack later sees another man giving her flowers and kissing her.

After Jack's death, the Pearsons look for a new home. Kevin is frequently drunk; Kate gains weight and never completed her Berklee application; Randall criticizes Rebecca for not stepping up. She admits she barely has the energy to get out of bed and wonders what would have happened if she had agreed to buy the house Jack showed her months before the fire. Randall is accepted to Howard, but turns it down because his family needs him. In the present, Randall tries to effect repairs on a recreation center near his Philadelphia building; William's friend ChiChi tells Randall that focusing on the community's problems does not make him part of the community.

As a child, Rebecca disdains the role of housewife. The day she and Jack have planned to have their second date, her high-school boyfriend Alan arrives, three years after she declined his invitation to move to London. Jack returns home; he and his mother leave Jack's emotionally abusive father. Rebecca agrees to relocate to New York City with Alan, but confides in his mother that she has feelings for someone else. Rebecca goes to see Jack; as he washes dishes, she helps him and suggests they drive to Los Angeles together. In the present, the Pearsons love Kevin's film.

Jack and Nick's youth is shown in reverse-chronological order. When Nick is born, Jack's father is a supportive non-drinker whose own father is emotionally distant. Nick is born at 11:58 pm on October 18; Jack's father exhorts him to protect Nick. Jack believes seven-year-old Nick can be heroic. Nick stands up to their abusive father; Jack supports Nick and experiences tachycardia. When Nick is twenty-one, October 18 receives the fifth position in the first Vietnam War draft lottery. Jack plans to smuggle Nick into Canada, but Nick decides to prove himself by complying with the law.

In 1998, Randall skips prom after Allison's father rejects him because of his race. Sophie brings a drunk Kevin to Miguel's. Miguel buys Rebecca a piano and handles some home maintenance; he told Jack he would look out for the Pearsons if Jack died. Rebecca suggests Kate use music as an emotional release, but Kate is not ready. Young Toby suffers anxiety and depression; his humor helps his mother's depression. His mother and a therapist help him regain functionality after Josie leaves him.

When the Big Three are young, Jack is injured boxing; Rebecca asks him to stop, but later supports it as a needed emotional outlet. To get closer to his father, Randall pretends he has been bullied, so Jack will teach him to box. In the present, Beth has an outburst, struggling with unemployment and her daughters' Girl Scout cookie sales. Randall fails to win over his rival's constituency at a black church, partially because he lives all the way in Alpine, New Jersey. Kevin leverages his South Korean fanbase to help Randall campaign in Koreatown.

Serving in Vietnam, Jack wants a struggling Nick transferred to his unit, but commanding officer Major Dawson refuses because brothers are not normally assigned to serve together. A man named Bao transports Jack back to his base; Bao apparently participates in the manufacture of land mines and admits to "sometimes" being Viet Cong. At night, Jack sees the woman wearing the necklace; she runs away. Dawson gives Jack two weeks with Nick. Rebecca and Jack drive to Los Angeles for her singing audition. They are intimate, but Jack will not speak of his nightmares.

During the Vietnam War, Jack's unit celebrates Thanksgiving. Jack treats an injured boy whose mother gives Jack the necklace, but Nick refuses to assist; a villager betrayed Nick's first commander, resulting in his death. In 1997, Miguel spends Thanksgiving with the Pearsons and worries that his ex-wife is distancing their children from him. Randall writes a college essay about how loved ones and strangers can affect one's life. William and Jesse meet at a recovery group meeting. Jesse opens up to William, then joins him and other musicians for Thanksgiving. Jesse makes it clear to William that he is single.

In the past, in Vietnam, Jack and Nicky come to blows and Nick abuses drugs. Nicky is obsessed with their "mission" to "kill." He disappears from camp and a boat explodes, apparently with an American aboard. In the present, Kevin and Zoe visit the village, but learn nothing about Jack or the woman. Their guide tells Kevin that Nicholas Pearson did not die in the Vietnam War; unbeknownst to them, Nicky is alive in Bradford, Pennsylvania.

On election night, the Pearsons wait for the results. The preceding seven weeks are depicted. Randall realizes his mistake; he spends time with his family and Beth decides the family should follow through on a Philadelphia church visit. Kevin asks Zoe to move in with him, which she does but without unpacking. While researching his uncle, Kevin learns Zoe dumped an ex via email; he fears she will leave him and they break up.

Young Nicky hopes to become a doctor who owns a house and a boat. In Vietnam, a drug-intoxicated Nicky takes Lanh, the boy whose foot Jack treated, to go "fishing" with grenades; the boat explodes, killing Lanh. For years, Jack ignores postcards Nicky sends to his office. In 1992, Jack receives a postcard at home; after telling Kevin to correct, rather than repeat, Jack's mistakes, Jack visits Nicky at his trailer in Bradford. Jack tells Nicky to stop contacting him; Jack wants to forget the war. Nicky is haunted by the sight of Lanh's grieving mother.

In 1992, an emotionally drained Jack returns from seeing Nicky. Rebecca takes Jack's place to bring Kevin to a signing by Pirates player John Smiley and is touched when Smiley tells her that Kevin researched his future professional home of Minneapolis for him. At the house, Kate and Randall make a mess constructing Valentines; Jack loses his temper and destroys a plate, but apologizes and starts a sequin fight. In the present, the siblings bring Nicky to a hotel. Rebecca arrives and recalls the weekend Jack saw Nicky.

In the present, Beth and Zoe visit Carol after she bruises her hip at work as a high-school principal. They cannot convince her to retire. In the past, a young Beth gets accepted into a prestigious ballet academy and hopes to become a pioneering African-American principal dancer. Her parents, Abe and Carol Clarke, work longer hours to pay her tuition. Four years later, Beth is dedicated, but struggles to keep up. Abe dies of lung cancer, shortly after retelling Beth the story of how she danced before she walked. Beth confronts Carol over taking away her dream and accuses her of being emotionally disconnected.

In 1982, toddlers Kate and Kevin soothe each other. In 1998, the Big Three graduate from high school. Kate, with no plans and upset that Kevin is moving to New York with Sophie, skips her graduation ceremony; Randall is his school's valedictorian. Rebecca has a panic attack over Jack's absence from the milestone; Miguel calms her. Miguel later takes Rebecca, in tears after watching old home movies, to a grief support group meeting. At a graduation party, Kate, Kevin, and Randall agree to stay in each other's lives.

In the hospital waiting room, tensions rise as the Pearsons wait for news on Kate and the baby. Randall and Beth bicker and cannot agree how best to obtain child care, especially after learning Rebecca and Miguel are considering relocating to California for Kate. Kevin is hostile to Madison, whom Miguel encourages to find her own way to support Kate; Madison later retrieves a Ruth Bader Ginsburg doll Kate bought as a gift for her baby. Zoe hears out Kevin's explanation of his behavior and indicates to Beth that she will stay with Kevin; Zoe later tells Beth that a water bottle Kevin obtained earlier actually contained vodka.

In 1992, the Big Three attend a school dance. Randall wants to study, but chaperones Jack and Rebecca insist he honor his commitment to escort Kate's friend Jessica. Kevin ropes a reluctant Sophie into a prank on the principal. Rebecca requests an old song to dance to with Jack, who never attended a dance.

In 1998, Kevin coaches Randall to successfully ask Beth out. She is overwhelmed when he wears a suit and takes her to an upscale restaurant that discriminates against them; she asks him not to call her, but he privately believes they will marry. Seven years later, they are a couple, but Beth has declined Randall's repeated marriage proposals. Beth chafes that Randall's life "consumes" them. Rebecca tells Beth that Randall didn't know his place in the universe until he met her. Beth and Randall agree to be equals; she accepts his proposal. On their wedding day, they write their vows together.

During the Big Three's childhood, Rebecca crashes the car and is hospitalized. Randall is especially worried about her and Jack ultimately brings the children back to the hospital before dawn. To Jack, Rebecca is the family's "engine." In the present, Rebecca dominates Kate's conversations with healthcare professionals about baby Jack. Kate is frustrated, but ultimately admits that Rebecca was a great mom; Kate affirms she wants Jack to have Rebecca's "magic" in his life.