Roseanne, at nearly 100 the oldest person in Roscommon mental hospital and possibly in Ireland, sets down her life story in ballpoint pen, hiding the pages under the floorboards. Meanwhile Dr Grene, the psychiatrist in charge, starts keeping a journal. The imminent closure of the hospital, with a move to new, smaller premises, leads him to make a belated review of Roseanne's case. Looking at the files, he suspects that she was committed for “social” reasons, as was once all too common, and that she may never have been mad at all.

Roseanne recalls how her father, the Sligo grave-digger, was sacked by Father Gaunt, the local priest, for burying an IRA man in the civil war, when IRA men were supposed to be excommunicated. In fact, Father Gaunt gave the last rites himself, but then blamed Roseanne's father for getting him involved. Gaunt goes on to wield a baleful influence over Roseanne's life, because her good looks are an evil temptation to decent Catholic boys and she's a hell-bound Presbyterian. “Morality has its own civil wars,” as Dr Grene notes.

Sebastian Barry's style is avowedly literary in intent. Roseanne records, as a child, watching her father in the tin bath: “Carbolic soap, that would have cleaned a greasy floor, he agitated into a suit of suds, that fitted him well.” Dr Grene, noticing a new wind farm, says, “I saw the windmills silverly turning, as one might say.”

There are literary conceits at work, such as the idea that we are all ghosts to ourselves, lacking self-knowledge just as we cannot see our true faces in the mirror, observing only a notion of how we look. There is also the idea that personal, family and national histories are often falsified. Roseanne, for traumatic reasons, does not remember that her father was originally a policeman. Ireland chooses not to remember the vanished southern Protestants, or, for that matter, the civil war.

But one key to The Secret Scripture lies in the words over Barry's name on the cover: “Author of the bestselling A Long Long Way.” A few chapters in, it becomes clear that we are in bestseller territory, as lurid melodrama is piled on lurid melodrama, improbable coincidence on improbable coincidence, while important plot shifts are obscured by passages of excited purple prose.

We start encountering daft potboiler slip-ups. On the shore in Sligo, Roseanne sees German bombers returning from Belfast one summer night, hundreds in tight formation. But the raids were in winter, the Germans never flew in night formation and they hadn't the petrol to go round the west of Ireland. Dr Grene says he read psychiatry at Durham - where there is no medical faculty. And he seems to have taken it as a first degree. You don't suppose Barry's gone and mixed it up with psychology, do you?

The big twist at the end is effective and powerful, but corny, which does rather go for the book as a whole. It is rewarding, but you feel it could have been cooler and subtler.

The Secret Scripture by Sebastian Barry
Faber £16.99 pp300

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