John Keith is an agent A.P.E.
The American Policy Executive is an ultrasecret organization, known only to a handful, that doesn't officially exist but which nevertheless employs agents around the world to take care of any job too beyond the traditional agencies. Keith is well aware how the acronym comes out and is not a little amused at the fact.
Using as his cover for his many trips around the globe, Keith is a public relations expert for Skinner, Maywell and Finch, a firm based in New York. In this role, which he actually does as that is how he gets paid, Keith can go virtually anywhere, including behind the Iron Curtain, as good P.R. is useful to everyone.
Keith is in his early 30's, a snappy dresser, fond of the ladies, and quite fluent in several languages, especially Russian which he speaks as a native. He is a tall, 6'1", well built man who sports a large powerful handgun because "who it hits, knows it."
He has been an agent for A.P.E. for a few years prior to the start of the series. He is well trained to "bluff, immobilize, hurt, or kill a man", a fact that is not readily apparent as he usually acts the part of a frenzied but harmless American businessman just out to make another buck.
This governmental agency is rather unique in the intelligence community. It has no known offices, no apparent administrative staff, and possibly not even a Director. Who gives the orders or decides who get assigned is not known to any of the agents. Keith, for one, knows more enemy agents that he does his own side. When he has to work with a colleague it is usually via phone or letter drop, seldom in person. Since he doesn't know the others or his bosses, he cannot reveal them if caught and tortured.
This means that John Keith is on his own when in the field. He knows if he isn't good, he will be dead. So far, he has been very good.