Carson Cooper and Audrey Davis are agents with the CIA.
Of the two, Cooper is the far senior operative in age, experience and position. As we meet him for the first time he is just arrived in Moscow to become the latest Chief of Station, a role often held by a younger man but now, in 1983, the situation in the Soviet Union required someone of Cooper's abilities. The fact he is deeply familiar with is that at his age with the Agency mandatory retirement restrictions, this would be the last role Cooper would fill before leaving the service. He is excited about the upcoming work.
Audrey Davis is and has been a totally different sort of agent. A beautiful woman in her mid-30s, married to a Soviet politburo member named Boris and mother of two boys aged 6 and 8, she is deeply undercover. To those in Moscow who know her, and there are a good number of people who are pleased to be acquainted with this friendly lady, she is Tatiana.
The two do not know each other when the first recorded adventure takes place but they will become quite close, platonically, as the events unfold and each will find his/her life depending on the other. That will create a bond that will be unshakeable. Even when the second adventure comes four years later and Davis and her two sons are back in the States and Davis has taken a role of instructor at the Agency and Cooper has retired to take up being a tree farmer of all things, they will remain as though they had a father-daughter relationship. Which means when one of them, Davis, has trouble, the other, Cooper, is there to help out.