Orczy Emma. The Elusive Pimpernel

First published in 1908, The Elusive Pimpernel by Baroness Orczy is the 4th book in the classic adventure series about the Scarlet Pimpernel.
It is September 1793 and French Agent and chief spy-catcher Chauvelin is determined to get his revenge for the previous humiliations dished out to him at the hands of the Scarlet Pimpernel.