Ronald Jones is a spy for Mr Smith.
Who Mr. Smith is, well, that is a very long story which is also quite a bit the ongoing mystery of the first recorded adventure so saying anything here would be quite a spoiler. It would also take a lot more work than I feel like taking on.
But back on Jones, we are given one very useful look into him and how he would become an unwitting operative in this promo:
"After a career in teaching, what Ronald Jones wants to do most with his retirement is travel. To get himself away from it all, relieve his chronic anxiety, calm his deep distrust of other people. Relax. Espionage is the furthest thing from his mind. As a young man, with everything still in front of him, he had spent time in Brazil. Now, forty years or more later, he decides to go back. He has money, no ties, and nothing to stay at home for. It seems a simple plan, easily fulfilled. Arrange an itinerary, book a one-way ticket, lock up the house, get to the airport.
"Then the enigmatic Mr. Smith pays a call.
"Tourism gives way to intrigue. His plans become disrupted by projects that at first pander to his language skills but become increasingly perilous. Jones is flown around South America to destinations of another's choosing, instructed by a Project Controller - human or robot? - and catapulted into a new and very different existence. Espionage. Mystery. Intrigue. Who is he really working for? What do they really want? And why? With no apparent experience of this new world, Jones is way out of his depth, and in mortal danger. Moody men in suits, shape-shifting female agents and spooks are suddenly his daily companions. Just how far do these people expect him to take things? And if he cooperates, will they ever bring him back from the edge? Evolving from a retired teacher into a spy - repurposed - his character and daily habits change, and faint recollections of his distant past materialize. Ronald Jones wanted to travel. He got far more than he had bargained for."
To my mind, playing roles almost as important than Jones, and a whole lot more intriguing, are the members of a team working for and then against (or are they in either case?): Chameleon, Latvania, and Pilot. That is not their real names, of course, just what Jones will come to call them and why he picked those names in a good part of the story as well.