A tragic and shameful moment in French history continues to have consequences in the present day in "Sarah's Key," the screen adaptation of the novel by Tatiana de Rosnay.
Julia Jarmond (Kristin Scott Thomas) is an American writer living in Paris with her husband, Bertrand (Frederic Pierrot), an architect who is restoring a block of apartments in Paris owned by his family. Julia learns that Bertrand's family obtained the building through less than honorable means; the original owners were Jews who were forced to sell in the wake of the Vel' d'Hiv Roundup in 1942, when the Nazi-affiliated Vichy government arrested over 13,000 Parisian Jews.
One of the victims was Sarah Starzynski (Melusine Mayance), a 10-year-old girl who tried to protect her younger brother by locking him in a cupboard in their apartment. Fearing for her brother's safety, Sarah escapes the crowded cycling stadium where the Jews are being held and tries to make her way back home.
Julia learns of Sarah's story while doing research on the Vel' d'Hiv Roundup, and her investigation teaches her a great deal about an event many in France are reluctant to discuss, as well as the links to Bertrand's family.