Orphan. Clock Keeper, and Thief... Hugo lives in the walls of a busy Paris train station, where his survival depends on secrets and anonymity. When his world suddenly interlocks—like the gears of the clocks he keeps—thanks to an eccentric, bookish girl and a bitter old man who runs a toy in the train station, Hugo's undercover life and his most precious secret are put in jeopardy. A cryptic drawing in a treasured notebook, a stolen key, a mechanical man, and a hidden message from Hugo's dead father form the backbone of this intricate, tender, and spell-binding mystery.