Etiquette and Espionage is a young adult novel that takes place in the same universe as Carriger’s Parasol Protectorate series. (It is the first part of the “Finishing School” series.) Our Heroine is a girl named Sophronia who has the kind of childish, Tom Sawyer type adventures that are the despair of any parent that is trying to turn their daughter into a “lady.” After an incident with a dumbwaiter and a trifle, Sophronia is packed off to an elite finishing school. 
 

Sophronia is not on board with the plan, until the headmistress taking her to the school turns out to be an imposter, and their carriage gets hijacked by “flywaymen” seeking a mysterious “prototype.”