This thrilling companion to Paolo Bacigalupi's Michael L. Printz Award winner is a haunting and powerful story of loyalty, survival, and heart-pounding adventure.

In a dark future America where violence, terror, and grief touch everyone, young refugees Mahlia and Mouse have managed to leave behind the war-torn lands of the Drowned Cities by escaping into the jungle outskirts. But when they discover a wounded half-man--a bioengineered war beast named Tool--who is being hunted by a vengeful band of soldiers, their fragile existence quickly collapses. One is taken prisoner by merciless soldier boys, and the other is faced with an impossible decision: Risk everything to save a friend, or flee to a place where freedom might finally be possible.