The book tells a dual narrative story set in two different periods—the present day and World War II. In the present day, the main character, Alice, is struggling to balance her roles as a wife, mother, and daughter while also dealing with her grandmother's declining health. Meanwhile, the World War II storyline follows Alina, a young Polish woman living under Nazi occupation.
In the year 1939, Alina lives on a family farm in southern Poland. Her heart belongs to Tomasz Slaski, a local boy who wants to be a doctor. Their love is tested when Tomasz leaves for Warsaw to pursue his studies just weeks before the Nazis invade Poland.
Under the occupation, Alina's family suffers greatly as the Nazis seize their farm and resources. Despite the hardships, Alina clings to the hope that Tomasz will one day return. However, when Tomasz does come back he reveals that he was forced to join the German army. Aided by a Jewish doctor named Saul Weiss and his wife, Tomasz managed to escape Warsaw and has been hiding the family from the Nazis.
Alina and Tomasz rekindle their relationship but their reunion is fraught with danger. Tomasz shares a plan with Alina of escaping the Nazi-occupied region and seek safety in Russian territory. He carries a film canister that contains evidence of the atrocities at the nearby Auschwitz extermination camp.
Their plans are jeopardized when an informant alerts the German army. Tragically, Dr. Weiss witnesses the execution of his entire family. Tomasz agrees to switch identities with Dr. Weiss and bids them farewell promising to find Alina.
After they arrive at the Russian-occupied zone, Alina discovers she is pregnant. Consequently, Saul and Alina decide to marry each other under false identities to prevent social stigma. They accompany British agents to England and eventually make their way to the United States where their daughter Julita is born. They live as friends without consummating the marriage for over fifty years until Saul dies. Julita grows up unaware of her true heritage and eventually has her own child, Alice.
Alice forms a close bond with her grandmother but struggles with her challenges as a mother. When Alina has a stroke, she urges Alice to travel to Poland and unravel a long-held family secret. Alice discovers the identity switch between her grandfather Saul and her biological grandfather, Tomasz. She learns that Tomasz sacrificed himself to protect Alina while Saul assumed his identity. Overwhelmed by this revelation, Alice visits Tomasz's gravesite before returning home. Sadly, Alina passes away shortly after Alice's return. In a final act of love, the family takes the grandparents’ ashes to Poland.
