I had an idea about what would happen in Turncoat, the new novel by Anthony J Quinn. I was wrong. I’m not unhappy to be wrong. The first chapter indicates action: a thriller with bullets and guns at every turn. Instead we take a pilgrimage to Lough Derg in Donegal and spend our time dodging Mass and rations of black tea. Come expecting surveillance machines crackling with intelligence atop Divis Tower, get served something altogether more ambiguous and the better for it.

Desmond Maguire is a detective, a Catholic in the RUC in the years immediately before the Good Friday Agreement. A turncoat to his community and a second-class citizen among his professional peers, he grasps for the truth and tries to foil the IRA and its rival republican groups. One of these groups stitches him up good and proper and all of a sudden he has the press, Special Branch, his own guvnor, a shadowy and powerful committee and one or two in holy orders after him. He receives instructions to flee to the island, seeking his own truth and hiding among rich ritual and tradition. But this is no sanctuary, adding spiritual danger to the physical and psychological danger that Maguire has been surfing his entire professional life.

The rather dreamlike, unreal feel to the middle section of the novel (partly because of Maguire’s use of alcohol added to the pilgrimage programme’s deliberate lack of sleep for its participants) is increasingly unsettling as we realise that many of the pilgrim population have their minds on Maguire rather than on strengthening their faith. It’s a psychological process that strips down Maguire’s defences as he tries to strike the right balance between what he knows to be true, what he knows he has lied about, and the lies told to him that he has chosen to believe. But, as Pilate once asked: what is truth?

What we learn is that spying seems to be part-taught, part-understood: a life lived on the border between waiting and acting spontaneously. Maguire knows how to do some of this but spends the rest of the time finding solace in not-so-hidden swigs. He identifies most of those who are pursuing him, but has time for none but a siren called Perpetua who is interested in him for his soul. There’s even a ghost, coincidentally called Marley, just to nail down that there is nothing here that can be taken for granted. Confusingly there is a bit of a showdown between Maguire and his ghost…and by this point I’m finding it a bit superfluous because I’m expecting a denouement that is psychological rather than physical. Then Maguire concludes that Marley is not Maguire’s ghost, or as he puts it, his double, and I realise that Quinn has been one jump ahead of we the reader, and perhaps of the IRA too.

I am not sure what we are to make of it all, and I’m glad about that. For while Maguire has been drinking and praying his way to purgatory, Quinn describes what’s going on back at HQ. Investigations are going on, with each of the different forces trying to get ahead. Quinn portrays a culture of intelligence and counter-intelligence but also a dullness as detectives live on the edges of their nerves, ‘prisoners locked together in a fortress of ignorance.’ And when it comes down to it, the Troubles were as much about power within each community as an historic battle between two communities. Who was in and who was out was the great divider – at any one time and when the music stopped.

The final pages provide a useful and convincing counterpart to the beginning. As to the two hundred pages in the middle – where does the real truth lie? Maguire almost found out, but he doesn’t know and neither do we. This surprising, unsettling, uncomfortable and beautiful book is the better for it.

You can get Turncoat from the Cafethinking bookshop.

Thanks to Anne Cater for the blog tour information and to No Exit Press for the review copy.