The thrilling conclusion to the epic middle grade fantasy trilogy from Katherine Applegate, the New York Times bestselling and Newbery Award-winning author of The One and Only Ivan (now a major motion picture!), The One and Only Bob, Wishtree, and Crenshaw!

In the beginning, Byx’s original quest was to discover if there were more of her kind, or if she was destined to become an endling—the last dairne alive. She did indeed find more dairnes, and along the way she also created allies among other creatures in her world, including humans, felivets, raptidons, and wobbyks.

But Byx and her new friends soon learned that it wasn’t just dairnes in jeopardy of extinction, but that everyone was at risk. With the world in unprecedented danger, Byx must rally creatures of all kinds to lead a revolution.