Dickson McCunn is a retired grocer.
Of all the occupations of those not trained in the spycraft of the cloak and dagger world, there are a couple which have stood out as totally incongruous with the idea of trenchcoat-wearing denizens of dark alleyways. One of those is certain that which McCunn proudly admits to. He ran a grocery store.
When we first meet McCunn, this 55-year-old man of Scotland is feeling extremely pleased with himself, proud that after some time he had made the momentous (for him) change of habit from using a straight razor to shave himself in the morning to using one of those new safety razors. He is quite satisfied looking in the mirror and not seeing "a countenance ludicrously mottled by sticking plaster". More than that, he calculates that had he been using the device which allows him to shave in five minutes versus the previous 20, he would have saved, in the years since he first started shaving at 18, 3,370 hours. This sort of calculation of what would seem a simple sort of thing is why he was able to retire when he did.
McCunn, we will learn over time, knows how to embrace and enjoy the smaller things in life.
In description, it is said of McCunn that his "was not an old face. The sandy hair was a little thin on the top and a little grey at the temples, the figure was perhaps a little too full for youthful elegance, and an athlete would have censured the neck as too fleshy for perfect health. But the cheeks were rosy, the skin clear, and the pale eyes singularly childlike. They were a little weak, those eyes, and had some difficulty in looking for long at the same object, so that Mr. McCunn did not stare people in the face, and had, in consequence, at one time in his career acquired a perfectly undeserved reputation for cunning. He shaved clean, and looked uncommonly like a wise, plump schoolboy."
Having recently (less than a week before) sold his small chain of "provision shops", McCunn is "comfortably off, healthy, free from any particular cares in life, but free too from any particular duties". He is pleased, of course, but also wondering if he was "going to turn into a useless old man". He has no idea how his life going to change soon thereafter.
A walking holiday will take him and a new friend to visit a supposedly haunted house complete with a singing ghost in an adventure which will conclude with them going up against Bolshevik assassins after a Russian princess. A simple invitation to a good meal for a couple of new acquaintances will lead to his helping protect a dethroned monarch from communist killers. And a innocent correspondence with that same leader will open the way to his again trying to save his friend's life from even more anarchists wanting to rid the world of all royalty.
It makes one wonder if McCunn did not at times miss his days of stocking shelves and handling ledgers.