Paris, 1885: Aubry Tourvel, a spoiled and stubborn nine-year-old girl, comes across a wooden puzzle ball on her walk home from school. She tosses it over the fence, only to find it in her satchel that evening. Days later, at the family dinner table, she starts to succumb to a mysterious illness.

When a visit to a doctor only makes her worse, she flees to the outskirts of the city, where she realises that it is this very act of movement that keeps her alive. So begins her incredible lifelong journey around the world . . .

From scorched sand dunes to snow-packed mountain peaks, from a bottomless well in a Parisian courtyard to the shelves of an infinite underground library, we follow Aubry as she learns what it takes to survive and, ultimately, to truly live. But it soon becomes clear that the world she travels through is not quite the same as everyone else’s.