Wow. That is what I have to say about this book. This is a great historical fiction book set in WWII that I think anyone would love. This is a mystery book of sorts, so if you plan on reading this book later on or you are reading it now, stop reading this post because I will most likely give something away that you don't want to know, plus the family roles will confuse you if you haven't read the book yet. Felicity and Derek are so adventurous and are determined to crack the code in which Felicity's mother and "father" are sending her "uncle" letters from Portugal/France. Felicity has moved from London to America and her "parents" have left her with relatives, supposedly going back to London to continue working. Her "uncle" is keeping secrets from Felicity and is trying to protect her, but things aren't going well in that department. Felicity and Derek finally figure out that Felicity's parents are working in France as British Intelligence Agents. Felicity's "uncle" finally stops hearing from her "parents" and Felicity is told the truth she already knows from her "uncle" as well as who her parents really are (her uncle has been acting like her father and her actual father is the brother of the man who she thought was her father and was acting as her uncle; her mother was the only one that stayed in the same role, although she was married to Felicity's father and Felicity's "father" at different times). This book was all very complicated but really outstandingly great. I think that this book could easily win the Newbery.