"Aspen (the hostage prince) and Snail (the midwife's apprentice) must gather an army to face the Unseelie forces that want to destroy Aspen's home country"--,Provided by publisher.

The war that Prince Aspen and midwife's apprentice Snail started by accident is at hand. The Unseelie Army, the evil side of Faerie, will soon invade and destroy the Seelie kingdom. And Aspen is, after the death of his father and brothers, the Seelie King. Snail, his first and only friend, is the only one who can raise the army Aspen needs: an army of changelings, like her. First, however, she has to convince the mysterious, dangerous Professor Odds, the changelings' leader, who has a destructive plan of his own.