The development of crime series follows many patterns. Some burn brightly on debut, too brightly perhaps, and then fizzle out quickly. In others it takes the writer as many as half a dozen books or so to find the right place in the universe for their characters when the series can take on the mantle of greatness - Robert Crais' Elvis Cole novels spring to mind.
Others ride a rollercoast of quality as the author struggles to maintain excellence over the course of a dozen books. A few, Donna Leon among then, manage to pull of this most difficult feat and sustain brilliance over the course of a decade or more.
It remains to be seen exactly which category Brian McGilloway's Benedict Devlin series will fall into, but what I do know after two books, Gallows Lane and the debut Borderlands, is that he has made an extraordinarily strong start.
I read one (very positive) review of Gallows Lane that suggested these books would benefit from the inclusion of a map of the Donegal North/Republic border area, and I would heartily agree. The geography of this cross-jurisdictional area is critical and all the flitting back and forth can get a little confusing.
But while readers may struggle to locate that arbitrary line on a map that has been so critical to British and Irish politics over the last 80 years, they will have no such trouble in imagining the lands it divides. McGilloway's prose paints vivid, atmospheric pictures of this dark green land that hides its secrets and its ancient tensions, as well as the modern phenomenon of social exclusion.
While the Donegal border between North and South is not quite the wild terrorist-ridden frontier of South Armagh, so brilliantly brought to life in Toby Harnden's Bandit Country, it is still a place which offers ample opportunities for criminals to slip back and forth evading the forces of law and order, be they represented by Benedict Devlin, McGilloway's Garda Inspector or Jim Hendry, Devlin's counterpart across the border with the Police Service of Northern Ireland. It is also still a place where the IRA exists, either as a keeper of secrets or as an extra-legal keeper of the "peace". And certainly as a protector of its own residual interest in a case.
The IRA is only a peripheral minor player in Gallows Lane, but the story provides a chilling reminder of how powerful and dangerous that organisation can be, even if it is no longer actively engaged in terrorism.
Instead the crime here is rather more of the close-to-home variety - robbery and murder - and Devlin finds himself knee deep in both, as first a young woman is abducted from a night club and killed in a building site, and then a man returning to the South after a period at Her Majesty's pleasure in the North is found crucified in the garden of a wealthy man, close to where an IRA arms cache has just been found. Assisted by Ireland's equivalent of the FBI Devlin begins to suspect that the two cases might be linked by a long forgotten armed robbery north of the border.
As Devlin deals with this major rural crime wave he is also put under more pressure by the news that his boss, who suffered family tragedy in the previous novel, Borderlands, is retiring and giving himself the opportunity to apply for a Superintendent's promotion.
As the body count piles up, and with it the stress and the sleepless nights, Devlin's health begins to fail him and he finds himself questioning his judgment as takes uncharacteristic risks and makes dangerous errors.
Devlin's fallibility is one of the charms of McGilloway's work. He is not the gifted maverick who crosses the line to get his man (although he does break the rules). Nor is the cliched departmental alcoholic struggling to hold his life together. Instead he is a good man with two children, working hard for his family and doing his best to find justice for those that who cannot earn it for themselves.
He is a far more rounded, human character than often found in detective fiction: sensitive, vulnerable, stubborn, brave and committed. And Gallows Lane is all the better for it.
And McGilloway is a fine novelist, an expert builder of solid, credible plots who keeps a strong command of twist and turn in what at times is a complex, muddied trail.
But more than that he is a very gifted writer, poetic in his tone and turn of phrase, artistic, like a watercolour painter, with his descriptive powers.
It is seductive, compelling combination: impeccable characterisation, beautiful writing and a first class narrative. Borderlands is a terrific book, Gallows Lane an even stronger sequel.
As I wrote earlier, it is too soon to know just how the series will develop, but if I were a betting man, I would be quite happy to take a chance that we will see a lot more of McGilloway and Devlin.