Holy Orders, By Benjamin Black. Mantle, £16.99

When the youthful-looking John Hannah was egregiously miscast as Ian Rankin's middle-aged detective Rebus on television, the author put the best possible face on it. But when the more rumpled Ken Stott took over, Rankin said that even Stott wasn't the Rebus he had in his mind. And now another literary Celtic sleuth is about to have a physical incarnation.

Gabriel Byrne has been filming a TV series based on Benjamin Black's 1950s Dublin pathologist Quirke – the hero of a sequence of books that has now reached its fifth entry. Over-familiar title apart, this latest book is one of the most persuasive, with a strong vein of melancholy. Previous virtues – notably a stunning evocation of mid-century Dublin – are here married to a new rigour in plotting. Earlier books in the series have taken a far more discursive approach, and the sharper focus here pays dividends.

The body of a journalist is discovered in the canal, and Detective Inspector Hackett once more inveigles his pathologist friend Quirke to help in the investigation. With a murderer on the loose, the two men begin to discern that the solution to the case lies at the heart of an institution all-powerful in Dublin – the Catholic Church.

From James Joyce onwards (with his description of Ireland as a "priest-ridden country"), the Church, with its immense wealth and political clout, has been a useful lodestone for novelists. Inevitably, it is even more so with the storm that has enveloped it in recent years because of the many abuse scandals. The latter shame is reflected here in a reminiscence of Quirke's own childhood in an orphanage run by priests, and there is a genuine sense of outrage powering Holy Orders.

Black (the alter ego of novelist John Banville) has always ensured that the Quirke books are beautifully written, but cogent storytelling is a newly added ingredient, with the once rather one-note pathologist now a multifaceted character. The Gabriel Byrne series notwithstanding, it's clear that the literary incarnation of Quirke is going from strength to strength.