The 1935 photograph shows Israël and Hélène Malowanczyk standing on the balcony of their second-floor apartment at 118 Avenue Parmentier in Paris’s 11th arrondissement. The couple – he a hatmaker from Poland, she a French dressmaker – are smiling. Like almost all Parisians at the time, they rented their home, a two-room flat where they lived with their two young daughters. Five years later, after the Germans occupied France, the fate of the Malowanczyk family echoed that of many Jews in the city. Israël was deported, while Hélène and the girls fled to the southern “free zone” not under direct...