I Will Repay!

Juliette de Marny, last scion of an ancient ducal family, has sworn to ruin the man who killed her brother the Vicomte in a duel: Paul Déroulede, now a member of the Assembly. She learns four things while a guest in his house: her brother provoked the duel, though Déroulede did all he could to refuse the challenge; Déroulede is involved with a plot to free Marie Antoinette from the Conciergie; the mysterious Englishman known as the Mouron Rouge is a frequent guest at Déroulede's house; and Juliette has come to love the man she has vowed to destroy! (from GURPS Scarlet Pimpernel, by Lisa Evans and Robert Traynor)