Neville Conyers is an assassin for the British Secret Service.
Conyers is described as a "gentleman agent". He works for the British Secret Service, though each book has him assigned to a different section. He is an assassin and he is quite good at it.
While the hero of this series is listed as Conyers, there are really two protagonists, who happen to work at odds with eacy other. The main one, of course, is Conyers and the sections dealing with him are told from the first person. On the opposite side, though, is Anton Drakov, Director of the KGB's Dirty Tricks division, and a master at manipulation and his actions in both books, told from the third person, are every bit as important as Conyers.
Conyers is a character indeed. From the first paragraphs about his life, he takes on a unique, interesting, not altogether likeable roguishness. He starts out commenting on how he hates mornings but Her Majesty's government insists on his getting up. That sets the tone for his attitude towards authority and life in general. He does concede that mornings "wouldn't be so bad if they didn't come so early in the day." Little else is likely to get such a concession. The term gentleman used above really refers to his employment, not to his every day attitude. He can be churlish to his friends, imputant to his seniors, and chauvanistic to his lady friends. Through it all, though, he doesn't ever become rude enough to dislike - just enough to growl at.
Drakov, on the other hand, seldom varies. He is devious, conniving, manipulative and totally unmerciful when it comes to getting his mission done. Little else matters besides the mission, or so he acts. It could be, however, that it is the manipulation that is his biggest drive, not the results.
The two are not perfect matches as might be thought. They are not two sides of the same coin. Their differences, though, are what makes the conflicts so enjoyable.