On the July day that I sat down to write a review of a novel due to be published in September, I learned that it had just been longlisted for the Man Booker prize. This rather took the wind out of my sails. I felt as if I should say "Bound for glory!" and leave it at that.

Certainly the book invites the prediction. With 600 pages of metafictional shenanigans in relentlessly brilliant prose, The Bone Clocks hits lots of hot buttons, from the horrors of the Iraq war to the Eternal Battle of Good and Evil to the near-future downfall of our civilisation. It aims unerringly and from many directions at success. At one point it even includes a waspish book review of a similar literary project, and the temptation to quote is irresistible: "One: [the author] is so bent on avoiding cliche that each sentence is as tortured as an American whistleblower. Two: the fantasy subplot clashes so violently with the book's State of the World pretensions, I cannot bear to look. Three: what surer sign is there that the creative aquifers are running dry than a writer creating a writer-character?"

The review is too nasty to be just, but its self-protective mockery does provide a good example of an outstanding quality of the book: self-consciousness. In its vast inventiveness, its exploitation of trendy pop-cult stereotypes (soul-sucking vampires, anyone?), its jaunty hops between holocausts, the novel reminded me of Michael Chabon's The Amazing Adventures of Kavalier and Clay and The Yiddish Policemen's Union; but where Chabon is genuinely freewheeling, Mitchell's daring is somehow anxious. He watches his steps, always. Reading Chabon, I'm carefree; reading Mitchell, I feel cautious, uncertain. The story is narrated in the first person by five very different voices, at six different times from 1984 to 2043; among them a 15-year-old girl writing in the general tone of a Young Adult thriller, a consummately self-parodic prick of a writer writing in anglo-mandarin who bears more than a passing resemblance to Martin Amis (one novel is called, ahem, Desiccated Embryos), and a semi-immortal bodyshifter.

I find these radical shifts of time and person difficult, and, though willing to suspend disbelief, am uncertain when to do so. Am I to believe in the hocus-pocus of the secret cult of the Blind Cathar in the same way I am to believe in the realistic portrayal of the death agonies of corporate capitalism – or should I believe in them in different ways? How many novels is it? If it is one, I just don't see how it hangs together. Or maybe its not hanging together is the point, and I'm not getting it. There you are: anxiety in the writer makes the reader anxious too.

In its temporal leaps, and in the stream-of-consciousness narration (or stream of self-consciousness), The Bone Clocks can be compared to Woolf's The Years and The Waves. But The Years is told in the past tense, and the voices that tell The Waves are always framed by it: Jinny said, Louis said … Here, in a novel deeply concerned with Time, there is virtually no past tense. Present-tense narration is now taken for granted by many fiction readers because everything they read, from internet news to texting, is in the present tense, but at this great length it can be hard going. Past-tense narration easily implies previous times and extends into the misty reaches of the subjunctive, the conditional, the future; but the pretence of a continuous eyewitness account admits little relativity of times, little connection between events. The present tense is a narrowbeam flashlight in the dark, limiting the view to the next step – now, now, now. No past, no future. The world of the infant, of the animal, perhaps of the immortal.

While learning how it is that some of the characters are, indeed, more or less immortal, we get a glimpse of a scene that to me stands out in silence from the jangle of dazzle-language and the kaleidoscopic tumult of imagery and filmic cliche. We see it again just before an extended climactic orgy of violence. Nothing in the plot appears to depend directly on this vision or refer back to it, yet I came away from the book with the sense that it is the still centre of all the frenetic action.

"The Dusk," says Arkady, "between

life and death. We see it from the

High Ridge. It's a beautiful, fearsome

sight. All the souls, the pale lights,

crossing over, blown by the Seaward

Wind to the Last Sea. Which of course

isn't really a sea at all … … a west window offers a view over

one mile or a hundred miles of dunes,

up to the High Ridge and the Light of

Day. Holly follows me. "See up there?"

I tell her. "That's where we're from."

"Then all those little pale lights,"

whispers Holly, "crossing the sand,

they're souls?"

"Yes. Thousands and thousands,

at any given time." We walk over to

the eastern window, where an inexact

distance of dunes rolls down through

darkening twilight to the Last Sea.

"And that's where they're bound."

We watch the little lights enter the

starless extremity and go out, one

by one by one.

Sketchy as it is, this has to me the quality of a true vision. For all the stuff and nonsense about escaping mortality by switching bodies and devouring souls, death is at the heart of this novel. And there lies its depth and darkness, bravely concealed with all the wit and sleight of hand and ventriloquistic verbiage and tale-telling bravura of which Mitchell is a master. Whatever prizes it wins or doesn't, The Bone Clocks will be a great success, and it deserves to be, because a great many people will enjoy reading it very much. It's a whopper of a story. And in it, under all the klaxons and saxophones and Irish fiddles, is that hidden, haunting silence at the centre. Behind the narrative fireworks is the shadow that, maybe, makes it true.

• Ursula K Le Guin's The Unreal and the Real is published by Gollancz. To order The Bone Clocks for £15.49 with free UK p&p call Guardian book service on 0330 333 6846 or go to guardianbookshop.co.uk.