I realized half-way through that this book reminded me a good deal of *Code Name Verity*, another book I liked very much, a YA about two heroic girls in WWII, each doing dangerous work, with the more heroic of the two dying as the other watched, near the end. Even having two different viewpoints was similar, though *Nightingale* switched back and forth frequently. It's a painful read at parts ... and (spoiler alert) I found myself wondering if it was necessary that it was kept secret that the first-person narrator, in present day, who has been invited to France to attend a ceremony celebrating the heroic women, is the sister Vianne instead of the more heroic Isabelle (the eponymous heroine). But I realize it had to be so, so that we don't know Isabelle dies in the end. Toward the end of the book, the atrocities committed by the Nazis came at me like a jackhammer ... but felt (wretchedly) true. Some of the metaphors are so spot on, from page one: "My skin has the crinkled appearance of wax paper that someone has tried to flatten and reuse"--genius because that tells us not only what this woman looks like, and how old she is, but the fact that she's the sort who is so thrifty she would reuse wax paper. A lovely first line: "If I have learned anything in this long life of mine, it is this: In love we find out who we want to be; in war we find out who we are."