In 1935, ten-year-old Alex Maki of Bainbridge Island, Washington, is horrified to discover that his new pen pal, Charlie Laevy of Paris, France, is a girl, but in spite of his initial reluctance, their letters continue over the years and they fight for their friendship even as Charlie endures the Nazi occupation and Alex leaves his family in an internment camp and joins the Army.

"The last time Valerie was in Paris, she was three years old, running from the Nazis, away from the only home she had ever known. Now as a young woman all alone in the world, Valerie must return to Paris, to the bookshop and her sole surviving relative, her grandfather Vincent, the only person who knows the truth about what happened to her parents. As she gets to know grumpy, taciturn Vincent again, she hears a tragic story of Nazi-occupied Paris,...