This is the story of a an enquiring, 9-year-old, math wizard's search for a family.

Lepel, who lives a lonely life with his grandmother, uses his astonishing skill to keep inventory of millions of stolen buttons she traffics for a living, while he waits for his parents to return from a round-the-world hot-air balloon trip and restore his happiness.

One day, he encounters a young orphaned girl living inside a clothing display at the local department store. The two embark on a thrilling quest to reunite Lepel with his parents.