Wren is the weakest summoner on the continent — until the day he opens a door no one else can see, and finds Pebble, the smallest dragon ever hatched. Pebble can't breathe fire, can't fly far, and fits in a soup pot. But the Hollow Wyrm is waking, and the great beasts that should have stopped it are already gone. Armed with nothing but a kettle, a sketchbook, and a dragon the world calls useless, Wren walks from village to village, feeding what others fear and befriending what others hunt. To save the continent, he won't need to slay the Wyrm. He'll need to feed it — and prove that the smallest things are the ones that hold the world together.