Ben Nevis and the Gold Digger are private investigators.
Don't fuss at me for the pejorative nickname for Alison Gold - blame Ben Nevis who recounts these recorded adventures and he is the one who first introduces her that way. Then again, being a gold digger is pretty much the way that Gold earned a living for quite a while so ...
But first a few words about Nevis. Nevis comes from a family of crooks. In a bit of a flashback 26 years before when Nevis was 16 and standing in front of a judge about to go away for a couple of months for his crimes (Nevis, not the judge), we learn that Nevis's father and older brother were already doing hard time behind bars for a lot longer that a month or two. An appeal by his mother who had a plan in mind to keep young Nevis from following the family trade gets him reprieved but three weeks later he is being accepted by the Army. As he puts it, to keep from becoming a career thief, he was "on my way into a career that would end up with me being a killer! Not sure that was what the judge had in mind."
After a bit in the regular Army, Nevis gets accepted into the prestigious N14 branch of the SAS where he would serve for the maximum 10 years, followed by another decade working for the Met's Organised Crime Squad when he "got too old for N14". And it is important to note that during his N14 days, there were several instances where he was seconded for the odd job here and there for MI6. When he decided to go private as an investigator, he figured correctly that the long list of good contacts he had amassed would come in handy.
Now back to the Gold Digger. She is a 5'8 woman of medium build in her late 30s at the time of these adventures. She is Israeli by birth but when a teen, her parents and siblings were killed in a rocket attack by Hamas. Gold refused foster care and found her own way of making do, "hitting on wealthy men of a certain age and relieving them not of their sexual urges but of a good proportion of their wealth in cash or expensive gifts in order to live, which is where her nickname came from". She was smart enough to target married men with a reputation to lose so no reporting her to the authorities.
When she was old enough to be called in for national service, she found she liked being in the Army. She was soon spotted as having special skills of a wide variety and Mossad came calling. And they soon discovered more talents and she got moved into the highly specialized Kidon - trained assassins. When the maximum three years with the group came to an end, she found herself bored and decided to go into "personal security" in London, with a bit of gold-digging on the side. That is when she and Nevis reconnected (they had once worked a N14/Kidon job together in Iran). They are sometimes partners and always friends.
Oh, one other little point worth mentioning about Ben Nevis. He has a lot of friends in high places who think the world of him and trust him completely and well they should and all because he has definitely walked the straight and narrow for over two decades. Mostly. He does confide little things here and there, such as having a client for whom he handles security. One of his tasks is to do monthly bug sweeps of his offices in the City; said client being paranoid about being spied on by competitors. The point being? "The team I hire to do the sweeps have never found a bug in six years, but now and again I take one into his office and tell him we found it. Well on a retainer of five grand a month, wouldn't you?" That's Ben Nevis.