I was reluctant to read this one, having skimmed the back page and seen the word "execution". If you can't get your hands on the next book immediately, like me, it is a cruel, cruel cliffhanger.
This book has much fewer battle scenes than the previous book, and isn't focused as much around the war, although several important events happen to do with the war. Temeraire and Laurence return home in triumph only to find that a contagion has swept through the dragons in Britain. It was referred to in the previous book, and some things about the previous book are explained by it, which I thought was pretty good, although Novik isn't bad at continuity anyway and this is obvious stuff. Rather than be hailed as heroes and relax for a bit, they have to go in search of a cure for the other dragons.
I was glad that the women return to having a more prominent place in this book, particularly Catherine Harcourt. I was somewhat less pleased with the fact that she does cave and get married, when she gets pregnant, which isn't really in line with what the Corps think of it. I was glad, though, that Laurence's qualms about unmarried women having children remained. Such values are an important part of his upbringing and the era, so that makes sense.
The themes of the slave trade continued, too. It was good to see repercussions of it in their relations with other countries.
I'm of mixed feelings about the end. Of course I'm glad that Laurence and Temeraire do the honourable thing, both in going to France and returning, but I'm sad that they have to and I wonder what will come of it.