When a petty thief falls though a glass roof in his attempt to escape from the police, what should have been the death of him marks the beginning of a while new life. After his broken body is reconstructed by an ambitious young doctor, he is released from prison, and—with the help of Victorian London's extensive sewer system—he becomes the most elusive burglar in the city. He adopts a dual existence as a respectable, wealthy gentleman named Montmorency, and his degenerate servant Scarper. But Montmorency must always be on guard. The smallest mistake could reveal his secret and ruin both his lives.