Paris, 2024. A letter arrives from Warsaw. It was posted in 1944.Céline Moreau is sixty-one years old and has lived her entire life in her mother's apartment in the Marais. Her mother was Isabelle - a schoolteacher who hid eleven people in a cellar beneath her school for four years and who carried a dying woman's letter through occupied Paris and sent it east through the resistance network. Isabelle never told Céline any of this. She left it in a cedar box with a key sewn into a coat lining.When a seventy-nine-year-old letter arrives from Warsaw addressed to Isabelle, Céline begins making phone calls. The first reaches Zofia Kowalski in Warsaw: a historian of the Polish resistance whose mother Marta was the nurse who decoded the cipher the letter contained. The second reaches Anna Brenner in Munich: seventy-nine years old, carrying her mother Elsa's account of the German officer's wife who used the intelligence to warn thirty-three families in occupied Amsterdam.Three daughters. Three cities. Three portions of the same story that no single person has ever held completely.The Last Letter Home is the final novel in The Unbroken Thread, a four-part series following women across occupied Europe connected by a single letter. It is a novel about what we inherit from the people who loved us before we knew their full story, and about the patience of things left for the right moment.Each book can be read as a standalone. Together they tell one complete story.The Complete Series: The Paris Silence - Book One The Warsaw Cipher - Book Two The Amsterdam Promise - Book Three The Last Letter Home - Book Four - The Series FinaleFor readers of Kristin Hannah, Heather Morris, Kate Quinn, and Pam Jenoff.