I got to know David Ashton's stories about James McLevy "inspector of police" through dramatizations by BBC Radio Scotland on Radio 4. As far as I know the author first wrote a series of McLevy stories that were broadcast as short radio plays and then has combined several of the investigations to create this book. I recognized the investigations and as I read could hear the wonderful voices of actor Brian Cox, who plays McLevy, and Siobham Redmond who plays the feisty madam of the Happy Land brothel in Leith. There's a suggestion of a previous relationship between McLevy and Jean but it's never elaborated other than their mutual love of good coffee.
Ashton's writings evoke the seedy underworld that was Leith: the latter an area of dockland that later became incorporated into Edinburgh, which, well into the 20th century was not a place you'd want to walk in alone late at night.
The book has not only a great sense of place and but is also full of humour with dialogue that captures the speech patterns and colloquial language of the area. Some of the latter words will be unfamiliar to many but their meaning is often discernible from the way they sound. e.g., dreich = a dull, overcast day; to boak = to vomit.
A robbery, that may be an inside job; a turf war between Jean Brash and a competing brothel madam; secret agents connected with the American Civil War and a Spiritualist medium all provide threads in this very enjoyable book. The creation of characters and their interactions are the key joys of these stories, not just Jean and McLevy but also the latter's boss, Lieutenant Roach, as a caricature of the upright pillar of Presbyterian rectitude; Constable Mulholland who solemnly quotes his auntie Katie and novice policeman Ballantyne who saves the lives of insects he finds in the station. Real life Arthur Conan Doyle (who trained in medicine in Edinburgh) dots in and out of the story as an enthusiastic participant in the detective work.
I've read that there was a real Leith policeman called McLevy in Victorian times who was friendly with a local madam called Jean Brash, but that the author has fashioned their characters from his imagination.