'Who is this man, this Scarlet Pimpernel?' Each day this question grew more pressing to the rulers of the French Revolution. Only this man and his band of followers threatened their total power. Only this maddeningly elusive figure defied the vast network of fanatics, informers, and secret agents that the Revolution spread out to catch its enemies. Some said this man of many disguises, endless ruses, and infinite daring was an exiled French nobleman,...