For some of us, it seemed likely that John Banville would be awarded the Nobel Prize for a lifetime of work before he would ever find a Man Booker Prize jury willing to acknowledge any single one of his astringent and uncompromising novels. Such a recognition even made a certain sense in terms of the prospect of having the readership for his fiction abruptly widen. The risk of a Booker, so to speak, especially in late mid-career – the Irish author is now 60, with 14 published novels – would be to introduce him in a manner that did scant service to either the veteran writer or the newcomer reader. Akin, say, to launching into Marcel Proust via a middle volume of Remembrance of Things Past or James Joyce through Ulysses.

Regardless, last month a jury awarded The Sea the Man Booker Prize for 2005. How unexpected was their decision? The novel was originally slated for a March, 2006, release in North America, a slot that its being named to the short list in September did not affect. The Sea was the only one of the five short-listed titles not available in Canada when the winner was announced.

Here, then, is what the thousands of about-to-be-new John Banville readers can expect, and should also be prepared to encounter. Above all else, expect from The Sea a ceaseless tide of ravishing prose, the cadences of which are designed to slowly dissolve the shoreline separating the artificial exercise of recording felt experiences from the actual experiences themselves. Language is a force, almost an end, unto itself in Banville, and in addition to being preternaturally eloquent, he is ambitious for every sentence he commits to print. Keep a dictionary handy, and be ready to reread passages either for their sheer beauty or, on occasion, to better appreciate their layering.

"I could hear faintly from inside the house," begins a typical sentence in The Sea, "the melting-toffee tones of a palm court orchestra on the wireless, and I pictured Mrs. Grace and her husband dancing together in there, sweeping around the furniture, she with her head thrown back and her throat bared and he mincing on his satyr's furred hind legs and grinning up into her face – he was shorter than she by an inch or two – with all his sharp little teeth on show and his ice-blue eyes alight with mirthful lust."

As for what debutante readers should be prepared to encounter, that same sentence offers hints, especially its observations about the "satyr's furred hind legs" and "sharp little teeth." The waters of John Banville's prose are about as chilly as the actual sea off the coast of his native Wexford, in southeast Ireland, the unspecified setting for much of his recent fiction. Though he's a student of the Beckettian monologue, his novels disfavour, or maybe simply can't summon, the intimacy of voice that makes Samuel Beckett's characters so endearing. His gaze is more that of still another Irish writer, poet W. B. Yeats, and of late Banville has indeed, pace the famous Yeats epigraph, cast that cold eye on life and death equally.

The Sea of the title is, in fact, the "inexorable slow flood" of mortality. Max, the book's sullen narrator, is grieving the loss of his wife to cancer. A self-confessed dilettante, he has abandoned a vague career as an art historian to return, literally, to his childhood. This involves a retreat to a seaside villa, now a boarding house for the befuddled, where he once spent a summer in the company of the Graces, a wealthy family whose twin children, Chloe and Myles, became his sort-of friends. Max's often exasperating narrative shifts from meditations on his present despair to the evocations of past intrigues that comprise the novel's modest plot. His long-ago relationship with the Graces led equally to his sexual awakening and to the tragedy – a drowning, no surprise – that has shadowed his adult life. For this, Max blames what he calls the "gods," the random incidents, often unjust and nearly always inexplicable, that befall mortals.

The novel opens with a declaration: "They departed, the gods, on the day of the strange tide." Death and The Sea, fate and the curious "business" of human discourse: The elegant and acute patterning of metaphor and thought are what John Banville does better than nearly any other contemporary writer. Likewise, The Sea deepens his preoccupation with the elaborate workings of memory, along with the capacity of language to capture this activity. "Memory dislikes motion," Max declares, "and prefers to hold things still." Struggling to summon a lost name, he even cracks a rare joke: "No, it will not come – so much for Memory's prodigious memory."

So much as well for prodigious memory's ability to stave off that sea of oblivion, the novel suggests. "We carry the dead with us only until we die too," Banville writes, "and then it is we who are borne along for a little while, and then our bearers in their turn drop, and so on into unimaginable generations."

The vagaries of literary chance aside, if there is a reason why the 14th book by this brilliant but austere writer should please a jury enough to thrust it into a Booker-bright light – a novel that is, incidentally, no better than The Untouchable or The Book of Evidence or even Birchwood, first published in 1973 – it may simply be that the tone of wistfulness that pervades the narrative holds a pleasing note of consolation, and even of defiance. "And indeed nothing had happened," Max reports of another strange tide that nearly pulled him under, "a momentous nothing, just another of the great world's shrugs of indifference."

But here he is wrong, and the marginally warmer waters of The Sea somehow feel like the proof.