Leviathan by Scott Westerfeld

Amazon Description
This is World War I as never seen before. The story begins the same: on June 28, 1914, Archduke Franz Ferdinand and his wife are assassinated, triggering a sequence of alliances that plunges the world into war. But that is where the similarity ends. This global conflict is between the Clankers, who put their faith in machines, and the Darwinists, whose technology is based on the development of new species. After the assassination of his parents, Prince Aleksandar's people turn on him. Accompanied by a small group of loyal servants, the young Clanker flees Austria in a Cyklop Stormwalker, a war machine that walks on two legs. Meanwhile, as Deryn Sharp trains to be an airman with the British Air Service, she prays that no one will discover that she is a girl. She serves on the Leviathan, a massive biological airship that resembles an enormous flying whale and functions as a self-contained ecosystem. When it crashes in Switzerland, the two teens cross paths, and suddenly the line between enemy and ally is no longer clearly defined. The ending leaves plenty of room for a sequel, and that's a good thing because readers will be begging for more. Enhanced by Thompson's intricate black-and-white illustrations, Westerfeld's brilliantly constructed imaginary world will capture readers from the first page. Full of nonstop action, this steampunk adventure is sure to become a classic.

I had heard about this book long before I read it.  It sounded interesting, but not interesting enough to get.  And then my book club was reading it, so I got it...and loved it!

Prince Aleksander is on the run from the Germans. With his parents dead, he flees to a secret safe house in Switzerland. Deryn Sharp is disguised as a boy named Dylan, so she can fly. When the ship she works on crashes on a Switzerland glacier, things don't look good. Until she meets a mysterious boy named Alek... Alek is a clanker; Deryn is a darwinist. But when they work together, they might just be able to find a way off of the glacier. A steam punk fantasy about World War one that never was...

Besides the amazing plot, this novel is also beautifully written.  The second novel in the series, 'Behemoth,' is just as good, and the third and final book in the series, 'Goliath', comes out September 20, 2011!

Market: YA
Sensuality: None/Mild
Violence: Mild/Moderate
Language: None
Adult Themes: Death, War