Caroline recruits French actor Paul Rodierre to speak at a gala, and over dinner they learn Hitler has invaded Poland.

German biplanes attack Lublin, and Kasia flees with Pietrik and Nadia, witnessing the violence and bloodshed left in the attack's wake.

An SS man follows Kasia home from an underground mission, leading to the arrest of her family, Pietrik, and Luiza at the cinema.

Halina, Kasia, Zuzanna, and Luiza are crammed into a train car and transported to Ravensbrück concentration camp.

Fritz convinces Herta to administer her first lethal injection to a prisoner, and Herta chooses to remain at the camp.

Medical experiments begin on the Polish women; Kasia's leg is deliberately broken and Zuzanna is surgically sterilized without consent.

Luiza dies as a direct result of the experimental surgeries performed on her at Ravensbrück.

Kasia devises a plan to write coded messages in urine and sends her first secret letter to her father listing the Rabbits' names.

Suhren gives Herta permission to track down and execute every surviving Rabbit before Allied forces can reach the camp.

The Russian prisoners trigger a camp-wide blackout, allowing Kasia and Zuzanna to escape onto a Swedish Red Cross bus.

British soldiers apprehend Herta at her mother's home in Düsseldorf after she attempts to kill herself in the bath.

Caroline travels to Paris to nurse Paul back to health, and they declare their love and plan a future together.

Rena returns alive, devastating Caroline, but Caroline eventually finds Paul and Rena's daughter Pascaline at a Paris orphanage.

Caroline partners with a magazine editor to raise money and organize the Rabbits' medical trip to the United States.

Kasia confronts Herta at her German medical practice, learns the truth of her mother's death, and reclaims the stolen ring.

Lilac Girls follows three women whose lives are transformed by the Second World War. Caroline Ferriday is a New York socialite who falls for a married French actor and dedicates herself to helping French orphans and later the Polish Rabbits. Kasia Kuzmerick is a teenage Polish girl who joins the resistance, is captured, and subjected to brutal medical experiments at Ravensbrück before escaping with her sister. Herta Oberheuser is a German doctor who chooses to participate in those same experiments, performing surgery on prisoners without their consent. As the war ends, each woman must face the consequences of what she endured and what she did. The story culminates when Kasia tracks down Herta in postwar Germany to learn the truth about her mother's death and reclaim what was stolen from her family.

The headline events of three women's lives shaped by World War II.

Paul defies instructions and delivers an emotional, forbidden speech at the gala, moving the entire crowd to tears.

An SS guard arrives at the Kuzmerick home, kills Kasia's pet chicken Psina, and warns the family about withholding food from the Reich.

Herta's aunt silently walks in on her husband sexually assaulting Herta in the butcher shop, then turns and leaves without a word.

Paul visits the French Consulate to seek a visa for his wife Rena, and Caroline volunteers to be a second sponsor.

Kasia completes her first underground mission, delivering a money envelope to a safe house under her resistance codename Iwona.

Herta arrives at Ravensbrück and talks Commander Koegel out of firing her, securing her position as the camp's only female doctor.

Herta discovers that Halina is a trained nurse and reassigns her from bookbindery to work directly in the camp hospital.

Fellow prisoners form a group called the Walls, hiding the Rabbits in crowded blocks and smuggling food to them through windows.

Kasia's father sends back a spool of red thread, confirming he received and understood her secret coded letter.

Regina and other Rabbits are called to the shooting wall and cry 'Long Live Poland' before they are executed.

Kasia and Zuzanna return to Poland by ferry and reunite with their grieving father, who confirms their mother is dead.

Kasia retrieves the book Nadia secretly hid for her and finds all ten of Pietrik's dance tickets tucked inside.

At the Lublin Castle memorial, Pietrik breaks down crying and holds Kasia close, then kisses her numb hand to warm it.

Kasia and Pietrik marry at the postal center; Nadia's dog Felka dies that same morning on Nadia's old doorstep.

Zuzanna and Serge marry on Caroline's Connecticut estate and introduce their adopted infant son Julien; Caroline receives a thick letter from Paul.

Behind the headline events of the war, smaller but equally important moments determined the women's fates. Paul's passionate forbidden speech, the killing of Kasia's pet chicken, and Herta's discovery of the Ravensbrück job advertisement all set the stage for the major conflicts ahead. Inside the camp, acts of quiet solidarity — food smuggled through windows, prisoners hiding the Rabbits, a spool of red thread sent through the mail — kept hope alive in the darkest circumstances. After the war, Kasia and Zuzanna return to a changed Poland and must grieve their mother while navigating an uncertain future under Communist rule. Pietrik and Kasia slowly find their way back to each other, and the novel closes with the joyful wedding of Zuzanna and Serge and a hopeful letter arriving for Caroline. Together these events fill in the texture of survival, endurance, and rebuilding a life after catastrophe.

The quieter but significant moments that shaped each character's path.

Caroline and Paul nearly sleep together at her apartment before a drunken David Stockwell shows up and interrupts them at the door.

Kasia spots her mother leaving a restaurant frequented by SS officers with Lennart and confronts Halina about their relationship.

Paul tells Caroline he is returning to Paris because it is the right thing to do, and they share a goodbye kiss on the rooftop.

Binz sets her dog on Kasia's former math teacher Mrs. Mikelsky, killing her; Kasia is forced to drag the body away.

Herta and Halina dance together to a Polish record in the hospital; Nurse Marschall catches them and resolves to take revenge.

Caroline sells treasured family silver heirlooms to an antiques dealer to keep her French Families Fund running.

Halina secretly visits her daughters in the camp and they play a dark game about what each would bring down to the shooting wall.

Fritz tells Herta he is leaving Ravensbrück and warns her that dangerous rumors about her closeness with Halina are spreading through camp.

Herta arrives at the hospital to find Halina gone; Binz informs her coldly that she will need a new assistant.

Caroline pressures her former beau David Stockwell, now at the State Department, to push for looser immigration quotas for refugees.

Herta is found guilty at the Doctors' Trial at Nuremberg and sentenced to twenty years in prison for crimes against humanity.

Kasia gives birth to a daughter she wants to name Hope, but Pietrik and her father call the baby Halina.

Caroline meets Paul's grown daughter Leena at a New York society ball and agrees to write to Paul for the first time.

Kasia refuses to leave for America without Zuzanna; a last-minute telegram arrives clearing Zuzanna for the journey.

Kasia drives home from Germany, gives her daughter her grandmother's paintbrushes, and finally slips into bed with Pietrik.

Every major shift in the story hinges on a decision or revelation that changes the course of events. Caroline's near-romance with Paul is interrupted by a drunken visitor, setting up years of longing and missed connection, while Paul's departure for France closes one door and leaves another agonizingly open. Inside Ravensbrück, small but charged moments — Herta and Halina dancing together, Halina's sudden disappearance — reveal the strange intimacies and brutal losses that war produces. After the war, Herta's conviction at Nuremberg and the birth of Kasia's daughter force both women to confront the weight of the past in very different ways. Caroline's unexpected reunion with Paul's daughter finally reopens the door to a future she had long abandoned, while Kasia's reluctant journey to confront Herta delivers the closure she has sought for over a decade. These turning points show how the smallest moments can carry the greatest and most lasting consequences.