Ask first after Philip Kovacs.

He is a man passing through life without ever touching the sides. 44, an English lecturer in Paris, he was married once but feigned adultery to extricate both himself and, although she didn't know it at the time, his wife; to retreat further into his intellectual sterility, his own self. And then one day he comes home to a strange perfume in his apartment. Nothing seems especially wrong until he notices his broken old typewriter has gone. His troubles are only starting, however, when he discovers his credit cards cancelled and loses his resident's permit to strange, pensive police inspector Laroche. Unable to prove his identity he fails to retrieve his new passport from the officious Post Office. Philip Kovacs' hermetic little world is imploding.

Ask now about Babalu dos Santos. The ebullient Bahian lives in the French capital too, stumbling accidentally across the well-kept secret of Parisian womanhood in the dark corner of a huge cemetery: Victor Noir. A young 19th-century journo and philanderer, Noir fell victim to his mistress' husband, his tomb now a shrine for the lovelorn to leave beseeching letters in his up-turned hat and avail themselves of the recumbent effigy that is always pleased to see them. For his part, Babalu has taken to liberating the notes and endeavouring to present them to their intended.

And now, in the middle of his disintegrating life, that hat yields a note for Philip Kovacs - one apparently composed on his own ruined typewriter.

39-year-old Adrian Mathews' debut novel is a heady, intoxicating read which, if it doesn't quite add-up, does enough along the way to convince you of a serious talent. The first half is particularly strong, hovering as it does on the fringes of both Magic Realism and Kafkian nightmare. Mathews' Paris largely eschews tourist sites, aside from the Pere Lachaise cemetery, with Victor's grave tucked away from Wilde and the leathered love-lizard, Jim Morrison. It's Babalu's nonchalance and easy charm that draw Kovacs in, warming the colder regions of both the city and the novel. But equally, it's Kovacs' fear of being out of control of the capital that gives the book its darker, uneasy edge. Mathews has made The City of Light his other main character.

It's in the later stages where gaps begin to show. The solution - and why is there always a solution? - to these dilemmas turns out to be remarkably prosaic. We hope for the Magic Realism to bleed through, for the promised erotic osmosis, but the author seems content to settle for word games, as though afraid to fulfil the hedonism of his early chapters. That's a shame, but there are still plenty of exceptional moments: Kovacs' confrontation with the laconic, philosophic Laroche in an amusement arcade; wonderfully promising (if slightly underused) psychotropic lilies; and a quite jaw-dropping gag on page 280. A little tricksy and less than the sum of its parts it maybe, but The Hat Of Victor Noir has parts enough to more than commend it to your attention.