For twelve years, Gertrude has been the only goblin in Pinnec Hill. The adopted daughter of the Captain of the Guard, she tries her hardest to live a normal life, ignoring the looks of disgust-and the rocks-thrown her way. But when an invading fleet of airships brings a goblin army crashing through the city gates, she understands why everyone fears her. The leader of this army is Wrendell, a powerful goblin sorceress, who burns the city to the ground in pursuit of one thing: the human princess, Beatrix. Gertrude's father tasks her with rescuing Princess Beatrix. With the aid of a cursed knight and a talking tree, Gertrude will encounter trolls and dragons, discover the true history of her banished people, and-as if that weren't enough-struggle with her own blossoming crush on a princess who doesn't trust her. No one expects much of a measly goblin girl, but Gertrude may be the only person who can save the kingdom.