The first two thirds of the book are  good spy thriller stuff with a mix of fact and fiction. At times character seemed to be sacrificed for the plot and it was often contrived. The character of Nathalie wasn’t very convincing. I think the author was reluctant to portray her as a nazi so it seemed like that was behind her when the novel started. But then her actions didn’t make sense.

It was difficult to care too much about the last third of the book with secondary characters having suffered far more than the main protagonists.