Mostly I enjoyed this book, and found it touching in parts. But I didn't like it as much as I thought I'd do.
Although writing a proper review about it without spoiling is a little bit hard, what I can say is that the "report" format didn't work too well for me. It wasn't bad per se, only it kept nagging me, often making me question whether this or that character would really act like they did; in turn, my suspension of disbelief was also challenged, and I don't enjoy it happening. Mainly, would a Nazi officer really let a prisoner write a manuscript as long as Verity's, considering that it was basically filled with very little information? Would any officer in any war do that, allowing a prisoner to toy with them by giving out intelligence morsel by morsel, through a literary piece of work? Such a deal would be understandable, sure, but only if there was more meat to it (and by meat, I mean information relevant to the Nazis).
On the other hand, the story was a good example of how resistance doesn't always look like it, can take many shapes and be carried in very clever ways, and how it may be found in the most unexpected places, too.
The novel didn't touch me as much as it touched other people, I suppose. Having read a lot of accounts and testimonies about the Shoah, concentration camps, and so on, I think I count among those readers whom it takes a lot to shock now. I guess it would have more impact on an audience younger than I, hasn't read as much about the WWII period, and hasn't erected emotional shields yet. (Because you definitely need those when it comes to studying about interrogation, camps, torture, and the likes.)