This isn't quite like any other Regency romance you're ever likely to read. Written in the first person by a thoroughly unreliable but utterly charming narrator (the titular "hoyden"), this witty, fast-paced novel takes the standard Napoleon at the borders/ports espionage tale and turns it on its ear.
There's no real point in going too deeply into the story since it's the characters (a well-travelled spinster, her male secretary and a conspicuously convenient nobleman) and the way that their very human reactions make an unholy mess of the plot, that gives this novel its charm. In its tweaking of well-worn and much beloved tropes this reminds me just a tiny bit of Stoppard's 'Rosencrantz and Guildenstern are Dead'. A must read for any fan of Heyer or Chesney.