Sarah's Key by Tatiana de Rosnay

In July, 1942, 10-year-old Sarah and her parents are arrested by the French police, who are cooperating with the German Gestapo to round up all of the Jews in Paris.  Because Sarah believes they will back home soon, she locks her younger brother in a cupboard, their secret hiding place, to protect him.  Sixty years later, Julia Jarmond, an American journalist living in Paris, is researching the roundup for a story she is writing for her magazine.  She becomes obsessed with learning what happened to Sarah.  The early chapters alternate back and forth between the past and the present.  It was a very moving and heartbreaking story, and I rate it 5 out of 5.  It is my 7th book for the New Author Challenge 2010.