The Navarone Series deals with a trio of agents working for the S.O.E.
The Special Operations Executive was a British intelligence organization created at the beginning of World War Two to engage in espionage, sabotage, and other activities as needed in enemy territories in Europe. Quite often the agents attached to this group were highly trained military officers and enlisted men but when working on an S.O.E. mission, they were there covertly and in civilian clothing making them spies under the Geneva Convention and therefore without any allusions as to their treatment and ultimate fate should they be captured.
The term "Navarone" is used to describe the activities of three key people and comes about because the island of Navarone was the location of the first mission, the one that brought the trio together in the first place. They would be reunited on that Greek island briefly for the second mission but would then leave to head to the actual assignment. The two remaining recorded adventures have nothing really to do with the Navarone location except in context of the three men.
The three men are Keith Mallory, Andrea Stavros, and Donovan "Dusty" Miller.
Mallory is a New Zealand officer serving with the British forces for some time, holding the army rank of Captain. He was before the war an avid mountain climber making him an indespensible man in the cliffs of Navarone. The fact that he had been operating in and around Crete and was an expert in that area made him even more valuable.
Andrea Stavros is a former Lt. Colonel in the now defunct Greek army, working with the Resistance and having no love whatsoever for the German invaders of his homeland. He is also a close friend and sometimes adversary of Mallory as the two had worked together before.
Dusty Miller is an American explosives expert who had signed up with the R.A.F. and was brought along because he was the key man for actually destroying the artillery objective of the first mission. Once he had proven himself to the others, it was natural that he remain with the team although his dour personality coupled with his pessimism always made him a cheery complement.
Mallory and Stavros like and dislike each other. Miller doesn't really like anyone, or at least trust anyone. Together they make a great team.