Reginald sends his 11-year-old daughter Bea to live with the Gregory family in Boston to keep her safe during the war.

Bea arrives at the Boston dock and meets the Gregory brothers, William and Gerald, for the first time.

The Gregory family brings Bea to their inherited island house in Maine for the summer.

Ethan gives Bea daily swimming lessons in Maine after she confesses she does not know how to swim.

Bea swims alone to the mainland from the island, fulfilling a promise she made to herself.

A family evening of Monopoly is interrupted by a radio announcement that Japan has attacked Pearl Harbor.

Reginald suffers a sudden heart attack and dies while Bea is in the US and unable to travel home.

William pulls Bea into the pantry and kisses her, beginning a secret romance between them.

Tommy, Millie's new husband, uses his connections to secure passage for Bea to return to England.

Before boarding the ship home, Bea urges William to move on and forget about her.

Ethan dies of a heart attack, and Nancy calls both William and Bea separately with the news.

William tracks down Bea's London address and appears at her door using Gerald's childhood coded knock.

William crashes his car while driving home drunk one Sunday morning and dies.

Bea flies to Boston for William's funeral and reunites with Nancy, Gerald, Rose, and William's children.

On Bea's last night in Boston, Gerald pulls out a ring box and asks her to make the Gregorys' home hers forever.

Bea Thompson is sent from wartime London to live with the Gregory family in Boston, where she forms deep bonds with all four Gregorys over five formative years. During her time in the US, she learns to swim in Maine, falls secretly in love with William, and finds herself deeply reluctant to leave when her mother arranges her return after the war. Years later, Ethan Gregory's death brings William unexpectedly to Bea's door in London, where the two revisit their past before quietly acknowledging it has no future. Bea loses William a second time when he dies in a car crash in Boston, and his death finally draws her back to the Gregory family. Reconnecting with Gerald in the aftermath of loss sets Bea on a new course, and their friendship deepens over years of correspondence and visits. Gerald proposes on Bea's last night in Boston, offering her the chance to make the Gregorys' home her own forever.

The headline events of Bea's two-family journey.

After Bea's departure, Millie lies in bed furious at Reginald and unsure she can ever forgive him.

On Bea's first evening, Nancy draws her a bath and the two begin to quietly bond.

Millie receives a telegram confirming Bea arrived safely in Boston but does not share the news with Reginald.

Asked to write about his most exciting summer moment, Gerald writes about Bea arriving from London.

While Christmas shopping with Nancy, Bea spots a stranger she thinks is Millie and shuts down with guilt.

During a Christmas phone call, Reginald feels unsettled rather than reassured by how comfortable and American Bea sounds.

Nancy watches Gerald teach Bea to dive and decides to host a dinner celebrating all three children's August birthdays.

While driving wartime ambulances with her colleague Julia, Millie confesses her deepest fear about Bea's return.

Bea, William, and Gerald sneak to the school chapel at night to hold a private funeral for Reginald.

During a visit to Columbia University, Bea tells the boys she will not attend university and will return to England.

For weeks, William and Bea sneak out of the house each night to lie together in the garden hammock.

After receiving the telegram about Bea's imminent departure, Nancy collapses in tears onto Ethan's lap.

On Valentine's Day, William comes home unexpectedly and brings Rose a bouquet of yellow roses.

Millie and Bea begin taking regular walks together and slowly open up about their years of distance.

Bea and Gerald buy back the Gregory family's house and island in Maine.

While Bea adjusts to Boston life, small daily moments—Nancy's bath-time ritual, Gerald's school essay, a guilt-ridden instant while Christmas shopping—reveal how deeply she is embedding herself in the Gregory family while drifting from her own. Back in England, Millie hides news from Reginald, drives wartime ambulances, and confides to a colleague the fear she cannot say aloud about her daughter's return. Bea's grief over Reginald's death draws her closer to William, and their clandestine romance deepens through nights in the garden hammock before her sudden departure. The years following Bea's return to England are shaped by Millie's choices and by Rose's quiet discontent in Boston, showing how the disruptions of the war ripple through multiple lives long after it ends. Slowly, through regular walks and honest conversation, Bea and Millie begin to close the distance that has separated them since Bea's homecoming. The full circle of the story is completed when Bea and Gerald buy back the family house in Maine, reclaiming the place that meant home to all of them.

The quieter moments that shaped Bea's two families.

Millie raises the possibility of bringing Bea home early, but Reginald flatly refuses to revisit their agreement.

Reginald and Ethan begin secretly exchanging letters and playing postal chess, a correspondence Millie knows nothing about.

Ethan confronts Nancy about continuing to bathe Bea, warning her that Bea is not their daughter and will leave one day.

William announces he wants to stay in Boston for the summer rather than go to Maine, and Ethan refuses.

After Reginald's death, Millie discovers his hidden letters to Ethan and nearly destroys them before her friend stops her.

Millie marries the younger Tommy without telling Bea first, angering Bea and straining their relationship for months.

Standing on the ship's deck heading back to England, Bea wishes the vessel would turn back toward the Gregorys.

William and Bea sleep together on his first night at her London flat.

Millie's unexpected early return from holiday forces William to leave without spending a second night with Bea.

Aboard the ship home after leaving London, William resolves never to tell anyone about his time with Bea.

Bea reflects that when the coded knock came at her door, she had briefly hoped it was Gerald, not William.

Gerald confronts William about his London visit, and William denies it ever happened, leaving Gerald furious.

Millie reveals to Bea that sending her to America was Reginald's decision alone, and that it was the right one.

Millie urges Bea to accept the Gregorys' Easter invitation, counseling her that young love is not the only love.

When Gerald asks what happened during William's London visit, Bea tells him that nothing did.

The earliest turning points—Reginald's refusal to let Bea return early, his secret chess correspondence with Ethan, and Ethan's warning to Nancy about loving someone else's child—quietly set the conditions for the novel's deeper conflicts. Millie's discovery of Reginald's hidden letters and her secret marriage to Tommy each widen the rift between mother and daughter, while Bea's departure on the ship marks her private acknowledgment that she truly belongs with the Gregorys. William's London visit becomes a secret multiple characters carry for years—his decision to lie about it to Gerald, and Bea's own choice to protect the memory by telling Gerald nothing happened, form the hidden fault line running through the novel's second half. Millie's revelation that sending Bea away was Reginald's decision alone finally allows both women to make peace with the past and with each other. Millie's counsel that young love is not the only love opens the door for Bea to fully pursue something real with Gerald. The pool ends with Bea's protective lie to Gerald about William serving as a final act of closure, freeing her to embrace her future with the family that has always felt like home.