Now. Onto the book that this is actually about. Since Behemoth is the second book in a series, I'd recommend you check out Leviathan first--the review for context, and the book itself to avoid spoilers.
Prince Alek and Deryn Sharp are now aboard the Leviathan together, and they are headed for the Ottoman Empire--Istanbul, specifically. This land at the edge of Asia and Europe has so far stayed out of the war, but can it last? The Clanker Ottomans are furious after a ship promised to them by the British was snatched up before delivery by a nervous Churchill. However, Dr. Barlow claims that her mysterious mission will somehow keep the Ottomans out of the war. Of course, nothing can possibly go that smoothly. From the beginning, diplomatic excursions are plagued by disasters--and there's the small matter of Alek's tutors feeling the need to escape the airship ASAP.
Behemoth introduces new places, new people, and new creatures for the next installment of Deryn and Alek's adventures in an alternate WWI universe where countries fight with genetically engineered creatures or huge, moving machines.