Leviathan

It's 1914 and Europe, armed with futuristic machines and biotechnology, is on the precipice of war. Prince Aleksandar is dragged from bed in the middle of the night to learn that his parents have been assassinated. A threat to the throne, Alex is on the run from the Clanker Powers who are determined to take over the globe with their mechanical machinery. Meanwhile another orphan, Deryn Sharpe, disguises herself as a boy to join the British Air Service. The British employ genetically engineered beasts, like giant whales, as their warships. When Alek and Deryn's paths cross, the two forge an uneasy alliance. One that will dramatically change the course of the Great World War...and their lives.