The story follows Stuart Horten, a ten-year-old boy who moves with his family to a new town. Feeling lonely and out of place, Stuart discovers that his late great-uncle, a famous magician, has left behind a mysterious inheritance hidden somewhere in the town.
As Stuart searches for the treasure, he encounters the eccentric and tiny The Evgorodians, who stand only a few centimeters tall. They have been living secretly among humans for generations, and Stuart becomes involved in helping them while continuing his hunt for his uncle's hidden legacy.