Crisscrossing romances is the approach of this novel. The opening scene is Sussex 2004, Colin and Eloise are in the midst of a romantic relationship and she's researching the Pink Carnation, a spy from the Napoleonic era, with ties to Colin's family.
Then we cross into the past with Gwendolyn Meadows, fearsome spinster and chaperone of Miss Jane Wooliston, in Paris, stalking Talleyrand. Then Jane receives news that her younger sister is missing from her school in England. They return to England and discover a second young miss has left the school, Miss Lizzy Reid, daughter of Colonel William Reid.
Gwen, who styles herself as the Purple Plumeria, and Colonel Reid become romantically entwined and marry at the end of the book. The missing schoolgirls are found and all ends happily ever after.