This is a very solid young adult book, with not too much romance shoehorned in. (That is to say, there is some romance, and it feels very shoehorny, but is on the brief side. This book in particular feels like it could have skipped the burgeoning of the feelings without in anyway detracting from the book.) I am waffling on the three or four stars right now - because I liked it enough to be interested in further books in the series without in any way falling in love with it.
But it is interesting, and there are real flashes of something exciting here. I am still undecided, and I retain the right to come back and tinker with the star rating later. Or after I'm finished writing the review and have figured out what I think.
So, it appears that the looming Great War in the this book is not just between the imperial alliances of Austria and Germany vs Britain/France/Russia. It is also between biology and engineering. The Germans, of course, have efficient machines - huge mechanical landcraft that strike my imagination something like a Star Wars walker. And in Britain, Darwin not only wrote about evolution, but pioneered genetic engineering, so the English battlecraft are giant living beings, sort of like flying jellyfish. And bats that poop razors.
Two young people are in the middle of this - Alex, the son of Archduke Ferdinand, suddenly in the crosshairs of dynastic politics. And Deryn, who passes herself off as a boy to join up as part of a flying crew. As the world lurches towards war, both have to fight in battles, and in the end, join forces.
It's not a deep book, and some things made me raise my eyebrows a bit, and oh, the flowering of new romance felt so unnecessary. But the ideas are interesting, and the characters may be a little flat, but they push the story along nicely. The world, though, that's what holds the most attraction. This is an interesting place.