Wendy Chen is a cybersecurity resource manager.
Guy Anderson is a cybersecurity sale representative.
When we first meet the two, they are both employed by Cyber Security Systems Ltd (CSSL), one of the largest cybersecurity consultancies in the world, working out of the bustling and exciting city of Hong Kong.
Chen is the "head of their Human Resources department in Asia, or as they preferred to call it now - Talent Calibration". While she is a native Singaporean with total command of three languages (English, Cantonese, and Mandarin), she has taken to her adopted city with a passion. Her job in Hong Kong is largely devoted to helping herd through corporate life the large number of "researchers" (their term for computer hackers) and keep them on the proper rails. "Many of them bordered on genius and this came with the high price of any thoroughbred, namely frail egos, mental instability, social awkwardness, chemical dependencies, and plain old eccentricity." This is particularly interesting in that the trouble that she gets herself and Anderson into in the first recorded adventure stems from her going off those same rails.
Anderson's role in CSSL is that of Senior Client Executive, also working in Asia, "looking after their larger customers". He is British, born and raised, but he also has become a huge fan of the Far East city he lives in. He is a gifted sales representative in that he can not only sell his company's services to banks, insurance companies, and governments, he can act as a knowledgeable liaison throughout the lifecycle of the relationship. He truly enjoys his work and has no plans for or desires to a change. He will get one nevertheless.
Now, neither of the positions for Chen and Anderson sound the least bit like they belong in the world of clandestine skullduggery. It is true that Chen in fact knows a whole lot more about computer hacking than she lets her employers know but she has no intention of entering the realm of cloaks and daggers - until she does. And on the day his life would change forever, Anderson got up with nothing more planned than a normal day doing normal work.
In a spur of the moment act, Chen does something that is totally outside her norm and she does so on a whim. [Saying what would be too much of a spoiler.] Why she does it is a mystery as she is doing it and will remain one for the remainder of the adventure. She herself will question why she did it, just as Anderson and others will, but a rational explanation will remain elusive.
The key point, though, is that her rash act will change both her life and that of Anderson to whom she will turn for help after the act. It will throw both of them into conflict with North Korea to start and into working with MI6.
Though Chen and Anderson are the main stars of these adventures, it would not be surprising to instead list as the real leading character Lee Hyo-joo, aka 'Talon'. As she is described by an MI6 agent to Chen and Anderson, she is "a North Korean military operative from the DPRK's army's AAA Command". He refers to her as "a highly skilled and an extremely dangerous woman". Considering the things that we can follow her doing, and he cannot, we know he has just touched the surface on this operative's nature. She shows that she can and will kill without any hesitation and while she will have to deal with uncertainty and risk, she will not flinch. She might growl a bit and have to deal with normal human emotions a time or two but when she makes up her mind to do something, I would not want to get in her way.