Nick McCarty is a cold-blooded assassin for the CIA.
Sometimes. By that I mean he is always an assassin. And a darn good one. And a very busy one.
It is just sometimes he works for the CIA. At least in the beginning of the adventures we have of him and we have a lot. He has his ups and downs with the Agency and sometimes he is ready to take on their mission and sometimes he finds he has to eliminate the people doing the asking. For that reason, it pays to ask from afar.
The adjective 'cold-blooded' is especially appropriate for McCarty even beyond that being the title of the series. The man has no feelings, or so it seems. He has and does kill with no hesitation and no regret. If someone in his opinion needs killing, he answers the call and does not have any paigns over it. Oh, on occasion he might rue the fact that a person had to be put down but never because he was the one doing it.
McCarty has been doing his job without error for quite a few years and plans on continuing it for many more. He has a couple of good reasons for wanting the work to continue. First, he enjoys it. Second, it pays extremely well. Third and most interestingly, it provides the plots for his novels.
McCarty is also a world-famous author of a series of best-selling graphically gory action adventure books about a cold-blooded assassin for the CIA named Diego. His picture is on the covers. He attends book signings. He is hoping for a movie or two to come from his stories. He gets away with it because no one can really believe that a man would do all the horrific murders he writes about and then have the temerity to do that writing. He finds their disbelief quite amusing.
Now, right when we meet him, some things will change. For one, he will show those close to him that he can have feelings, though in his own way. Someone hires him to kill a waitress he has just met and because he liked her and she was a good waitress, he looks into the who and why of the contract and decides against taking it. Then, knowing that someone else will just come along, he takes it upon himself to kill the contractor. Naturally that will spark a lot of trouble but since McCarty is now falling in love with the woman, Rachel, and her precosious daughter, Jean, he is more than willing to take on all those foolish enough to come after them.
As the series progresses, McCarty and Rachel and Jean and several more who join their group of very unusual people will have a lot of different adventures and McCarty will become very much a CIA go to guy for killing bad guys. All these missions will be quite, um, interesting.