Roger Brook is an agent for the British Prime Minister.
When first we encounter him, the year is 1783 and young Roger Brook is a 15-year-old student nearing the end of his academic career and facing the probability of being pressed into military service. He is very much against the idea, not because he is afraid or unwilling to do his duty to his country but, as he puts it, he is loath to have to unquestioningly obey those for whom he has little respect and whom he considers many to be dumber than he. In the first pages of the first recorded adventure he is being tormented by the school bully and though he has lost twice in fights with the older, taller, stronger student, Brook is unwilling to step back. He is not foolhardy or stupid - just quite determined.
That determination/stubbornness will play a major role in his life which will be depicted in 12 lengthy volumes, many of which actually span several years and numerous unrelated adventures. Brook will escape the fate his father, a British Naval Admiral, had decided for him and fled to pre-Revolutionary France where he will find the first of many, many adventures and fall deeply into love on numerous occasions.
Along the way he will become a most secret and effective agent for the British Prime Minister, William Pitt, and will be sent on numerous occasions into danger to find vital state secrets or to undermine one side in a conflict or bolster another side. He will work diligently to help preserve many of the nobles of France, winning some battles but losing many. He will be instructed to join up with an upstart French military officer named Napoleon Bonaparte and become a major player in that person's actions to better report back to Pitt.
And he will continue to let his emotions, be it love or lust, dictate many of his actions. Some will cause him great discomfort. Some will bring him increasing success and wealth. All will continue to feed the imagination of the young man in school who really did not like being told what to do.