At first glance, it may seem that Donal Ryan is returning to the well-proven territory of the 2013 Guardian first book award-winning, and Man Booker-longlisted, The Spinning Heart, or his much-praised The Thing About December of the same year. But as All We Shall Know progresses, we watch with growing fascination as he expands, not only his emotional range, but also his social sphere. The book builds on those earlier works to establish Ryan beyond dispute as one of the finest writers working in Ireland today.

The novel is narrated by Melody Shee, whose mother (a woman who “always smelt of French perfume and expensive leather”) made it a marriage-long project to undermine her mild, working-class husband (whose own characteristic scent is a mixture of “sweat, and something sharp and heavy, bitumen maybe”). This steady attrition drives a wedge between Melody and the father who not only adores her but is also the moral foundation of her world. “I appraised him coldly. What was he good for?” she says - and later, in her own marriage to a working man named Pat, she turns the same judgmental gaze on her own husband. “All you are to me is a tenant, I’d say to Pat. And he wouldn’t answer. A tenant who pays no fucking rent. And he’d open his wallet and throw whatever was in there at me.”

It wasn’t always like this. At one time, Pat had been desirable, one of those rugged, narcissistic boys to be found in any small community who, being good at sport, are not only popular with their peers but seem to pass through several happy, golden years before an unexpected but entirely predictable drift into dull middle age. Melody had fallen for Pat at a hurling match, after he was sent off for attacking a boy who had “said something smart” about her in school. He punched the guilty player to the ground before removing his own helmet “with one sweeping movement and his hair was wet with sweat and swept back from his forehead and the sun lit his face and his blue eyes blazed and they held mine and he pointed to his heart as he strode through the cool evening air towards the sideline”. Sadly, this sporting hero has “a fair shitty seed” in him and he and Melody cannot conceive the child they had hoped for.

Now she is lumbered with a husband she has come to despise and haunted by her betrayal, in her heady school years, of a depressed but highly imaginative girl named Breedie Flynn (her association with Breedie had prevented her from joining the in-crowd to which Pat belonged, so she abandoned her friend to casual bullying and self‑harm). Melody is alone, ashamed - and pregnant by another man. She is also troubled by her treatment of her simple, rather pious, but profoundly decent father. He too is alone now, in his neat home, waiting for her rare visits like a ghost at the front room window.

Into their world come an illiterate boy named Martin Toppy, the son of a famous Traveller, and another “tinker” child, a slender wisp of a girl named Mary Crothery. A relative of the Toppys, she is relegated to pariah after she abandons the husband to whom she had been married, with much ceremony, in a union intended to bring together two powerful English and Irish Travelling clans. While a vicious feud is waged around them, Martin and Mary play a vital role in Melody’s transformation from her mother’s contemptuous child into the daughter and friend Melody wants to be. They also raise vital questions about what it means to live with honour in the denatured postmodern world of “country people” (ie non-Travellers) and the closed kingdom of their own kith and kin. The erotic overtones of Melody’s friendship with Mary, too, raise interesting questions about the narrowing of sexual possibilities in small town communities.

It would be a bending of the classical definition to say that these figures are tragic - but in a way they are. As the book approaches its difficult conclusion, the possibility of healing, of atonement, is at least suggested by the narrator’s last, extraordinary gesture. Without disclosing the details of this final scene, it does not seem extravagant to claim it is worthy of Greek drama. That the tragedies of our own age happen in suburban semis, or on Travellers’ sites, does not make them any less cathartic - and Ryan’s choice of narrator, a character both deeply flawed and painfully guilty, shows him working in the great tradition of tragic fiction, his lonely adulteress coming to grief in the same shadowy spaces as Emma Bovary or Anna Karenina.