The story follows a young scientist in the contemporary world, who actually came from the world of dwarves, thanks to a magic potion, held by the Big Eater, ruler of the dwarves. The dwarf kingdom, Shuflandia, exists in a cellar of a library, and only the most obedient get the chance to grow to king size and inhabit the larger world. Once there, nobody wants to return to Shuflandia. Also, there are no women in Shuflandia.
Nathan Flomm, in order to avoid the humiliation of having missed out on a hugely successful business, assumes a new identity on Martha's Vineyard. He plots revenge when his former business partner moves to the same town.
To help his divorced neighbor claim a substantial inheritance, a family man poses as her husband. The ruse spills over into his career in advertising, and his recent promotion relies on his wholesome and moral appearance.