All authors want brilliant quotes from other authors for the back of their books. But to get William Boyd, David Mitchell, Michael Ondaatje, Zadie Smith and Joshua Ferris all offering the gushiest plaudits is surely the ultimate dustjacket dream. Geoff Dyer has achieved it with this new novel: “sort of like a postmodern Kingsley Amis”; “a haunting and frequently hilarious meditation on love and art”; “it drips with Dyer's derelict luminosity”. Derelict luminosity. Wow.

This is Dyer's first novel for 11 years. He is a writer's writer and critic's critic - clever, erudite and dashing - but please give your answers on a postcard, or maybe a very long letter, about what this novel is about.

The first part of Jeff in Venice, following the journalist Jeff Atman to the Venice Biennale, is engaging and funny: an insider's view of the art world at play. Dyer catches the whirl of parties brilliantly, the chatter and sozzled one-upmanship: “You came to Venice, you saw a ton of art, you went to parties, you drank up a storm, you talked bollocks for hours on end and went back to London with a cumulative hangover, liver damage, a notebook almost devoid of notes and the first tingle of a cold sore.” The keen-eyed reader will start recognising playful, and occasionally dark, parallels with Thomas Mann's Death in Venice.

Like Aschenbach, Jeff has his hair dyed. If Tadzio is the object of Aschenbach's obsession, then Jeff soon falls under the spell of Laura, a beautiful American. But whereas Aschenbach's lust was unconsummated, Jeff and Laura's is consummated over and over again. The weather is as stifling and Venice as labyrinthine and faintly threatening as it is in Mann's novel.

The affair rumbles on amid the buzzy parties. It's lovely to read but the plot doesn't really go anywhere. As in Death in Venice, beyond the chatter is a grounding belief in the power of art and beauty. There is a wonderfully still moment when Jeff registers the beauty of a James Turrell light sculpture. Relief comes when he steps from the heat into the dark sanctuary of churches.

For all his novel's lack of propulsion, Dyer is a witty and concise observer of landscapes: social, geographical and emotional. For instance, Jeff notes that neither he nor Laura mention meeting again. “A strange, modern form of intimacy - not Victorian at all - that made it easier to lick someone's ass than to ask when you might see them again.”

The last we see of Jeff in Venice, he is lying alone under the sweltering sky, a gull swooping over with a dead pigeon in its beak. For all the omens of disaster and obliteration, Jeff emerges unscathed.

Some kind of obliteration is more emphatic in the Death in Varanasi part of the novel, so distinctly different from the Venice bit that it feels bizarrely welded on. Varanasi is a kind of posh-hippyish destination in India where the first-person “I” narrator (Jeff? It's not made conclusively clear but we assume it is) is holed up trying to find some kind of meaning. Because Jeff and Laura have talked about Varanasi in the previous part of the book, we assume that this must be Jeff. Certainly, the journey started off as a journalism assignment.

But his hiatus there has become extended. He makes friends with a small bunch of travellers and stops shaving. He becomes ill, gets thin and subsists on bananas. He seems without purpose: he watches the locals' ceremonies, almost gets involved with some hippies, and becomes critically ill. He seems to be on some kind of spiritual quest.

There is no mention of Laura although, as in the earlier section, Dyer is adept at deconstructing the everyday, especially in a scene where his protagonist confronts a queue-jumper (ineffectually, because after emerging victorious he is perturbed that the queue-jumper doesn't seem to have noticed that he came off best). His decline accelerates when he is flicked in the face by the faeces-caked tail of a cow. He swims in the Ganges, sees a dead man and by the end is hallucinating wildly, possibly mortally.

This second part of the novel is indulgently aimless, beautifully written and freighted with a significance that is never made clear. All the way through there is a sense of being being kept at arm's length, not quite being let in on the deeper meaning or the cosmic joke (if there is one). But Dyer's eccentric charm and barbed perceptiveness will hook you to the end. Along with his “derelict luminosity”, of course.

Jeff in Venice, Death in Varanasi by Geoff Dyer
Canongate, £12.99, 296pp Buy the book

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