Leviathan is a young adult science fiction steampunk novel that takes place during World War I. Leviathan was written by Scott Westerfeld and illustrated by Keith Thompson in 2009, and it won the Aurealis Award for Best Young Adult novel. Westerfeld is a well-known author of over 20 young adult novels, including Leviathan and its two sequels, Behemoth and Goliath. The novel follows two teenagers from opposing sides of the war and develops the themes of Doing the Right Thing and the Perception of What Is Right, Resolving Differences Between Competing Groups, and The Consequences of Subterfuge.

This guide refers to the 2009 Simon Pulse eBook edition.

Plot Summary

Leviathan is the first book in a trilogy that takes place during the early days of World War I. In this world, the war is fought between the Darwinist world powers and the Clankers. The Darwinists, which include the British Empire, Russia, and France, rely on fabricated beasts, animals that are genetically engineered in a lab using Charles Darwin’s discoveries on how to mix DNA strands from different species. The Clankers, which include Germany, Austria-Hungary, and the Ottoman Empire, rely on intricate, diesel-powered machines that can walk and run at high speeds while firing machine guns and cannons.

The book opens the night Archduke Ferdinand of Austria-Hungary and his wife Sophie are assassinated. Their child, Prince Aleksander, is forced to flee his home in a stormwalker with a crew of four men, including his master of mechanics, Otto Klopp, and his fencing teacher, Wildcount Volger. The team spends weeks trudging toward the Swiss border, hiding in the forest and fighting off assassins who are trying to kill Alek. The young prince doesn’t understand why he is being hunted because he has no title or power due to his mother’s common blood. The assassins are relentless, however, and Alek is forced to suppress his fear and grief and learn to live on the run.

Meanwhile, Deryn Sharp dreams of flying and joining the Air Service. Only boys can be airmen, so Deryn disguises herself in her brother’s clothes, adopts the name Dylan, and joins the crew of the most famous airship in Britain, the Leviathan. To Deryn’s dismay, the Leviathan is adding another crewmember, a female scientist with a secret mission. Deryn is assigned to assist Dr. Barlow and fears that the woman will discover her true identity.

As Alek is sneaking through Austria-Hungary and learning about the plight of his common people, Deryn is hard at work aboard the airship. Every two chapters, the perspective of the story switches between the teens. Through various mishaps and adventures, Alek and his crew arrive at a castle in Switzerland. On their first night in the castle, Volger tells Alek that the Archduke legalized his marriage to Princess Sophie, making Alek the rightful heir of Austria-Hungary. That same night, the Leviathan falls to an attack from German airplanes on a glacier a few miles from Alek’s castle. The crash kills many crewmembers and damages the secret cargo Dr. Barlow brought aboard. Deryn learns that the cargo is eggs but doesn’t know what kind of creature is inside them.

Despite Volger’s warnings, Alek steals medical supplies from the castle and sneaks to the glacier to help the shipwrecked crew, meeting Deryn, who is disguised as Dylan). The crew takes Alek hostage, and Alek pretends to be a common Swiss citizen. Although Alek is a hostage, the teens get along well and become friends. Through some clever diplomatic moves, the Clankers agree to give the Leviathan food in exchange for Alek’s safety. By paying close attention, Dr. Barlow and Deryn discover Alek’s true identity but promise not to tell.

When the Germans return to finish off the Leviathan, Alek helps defend the airship, damaging his own stormwalker and giving away his identity and location to the Germans. In order for both groups to survive, they combine their technologies by adding the engines of the stormwalker to the living airship. Together, the crew of the Leviathan and Alek’s five-man stormwalker team manages to fight off and escape the German attack.

Deryn is then ordered to divulge any information she has about Alek. She realizes that she has feelings for Alek and would rather lie and disobey a direct order than put him in danger. Alek refuses to let her do that, and Deryn nearly reveals her identity to him before Dr. Barlow comes up with another solution. She tells the teens that Leviathan’s true mission was to deliver the eggs to the Ottoman Empire and correct a diplomatic disaster that Winston Churchill had created. She tells them that she is Charles Darwin’s granddaughter, and she can keep Alek’s secret from the ship’s captain. Alek and Deryn are relieved, but they are both shaken by the truth about Dr. Barlow. The story ends with Alek asking the eggs what they contain, but of course, the eggs do not answer.