Monstrous cunning

Tree of Smoke
by Denis Johnson
614pp, Picador, £16.99

Who'd have thought that Denis Johnson had this kind of whopping, mega-ton novel in him? His last, The Name of the World, ran to a mere 120 pages but still managed to sneak on to the shortlist for the biennial Irish Times international fiction prize. What made it so intriguing was that it seemed to be the work of a writer who, at some level, did not know how to write at all - and yet knew exactly what he was doing. Jesus' Son, his best-known book, is even skimpier: a collection of stories about strung-out losers unfolding in meticulously addled prose overspilling with transcendence, lyricism or just addledness. A writer, then, of distinctly American graininess: a metaphysical illiterate, a junkyard angel.

Needless to say, he is not everybody's cup of tea. After I'd recommended The Name of the World, a literary friend responded with an email contrasting Johnson's self-described "zoo of wild utterances" with Bellow's infinite loquacity. For me, the effect of the comparison was counter-productive: Bellow instantly seemed as old and venerable as George Eliot.

And now we have what is in some ways a Victorian novel: 600 pages, zillions of characters and a plot that offers a key to the variously contested mythologies of American involvement in south-east Asia (Vietnam, principally, but with substantial sections in the Philippines as well). What makes it a distinctly modern key is that, with every turn, the promised revelation is more securely concealed. We are talking CIA here; we are talking, more generally, about a literary mission that invites comparison with Don DeLillo, Robert Stone, Joseph Conrad (especially towards the end) and of course, Graham Greene (one of the characters is undecided whether he is a quiet American or just an ugly one).

However extensively the novel's story is summarised it is going to be sold short. It starts in 1963. "Tree of Smoke" is some kind of CIA project. Skip, an operative of uncertain status but intense dedication, is working for the Colonel (who also happens to be his uncle). Skip has an affair with Kathy, a Seventh-Day Adventist whose aid-worker husband has been kidnapped, possibly killed. Years pass. History - as they used to say of shit - happens. Kurtz-like, the Colonel's methods become increasingly unsound. At the sharp end are the seriously messed-up Houston brothers (who previously saw service in Johnson's first novel, Angels). Trung, a North Vietnamese - who once tried to assassinate the colonel - is being recruited as a double agent, but, at the same time, Trung's assassination is being plotted by the same guy - a German - who killed a priest with a blow pipe in the Philippines, back in 1963. Twenty years later, in Arizona, the Houston brothers . . . Ah, forget it. There may be no smoke without fire but in this case you can't see the wood for the tree of smoke, or something.

People and events loom out of the dense narrative foliage and then disappear. The writing can appear humdrum. Stuck in a quagmire of incantatory banality, the dialogue seems to be contributing nothing except its own capacity to keep on coming. But . . .

Whatever else might be said about my talents as a reader, my ability to quit is undisputed. I can give up on any book - and I never for a moment considered abandoning this one, even when it seemed to be going nowhere. Even though the story had disappeared like a path overrun by vegetation, the novel retained its uniquely slippery kind of traction.

Why? Because, at any moment it was capable of stumbling into the sharpest focus. Some kind of slanted truth seemed always close to hand. Let me give a tiny example and comparison. In one of Alan Hollinghurst's novels we learn that the characters all felt a bit "hectic" from drinking wine at lunch. So much is fixed so exactly with that single perfectly chosen word. Here is Johnson's swilled-out version of the same observation as applied to a sailor on shore leave in Honolulu: "He strolled the waterfront with the beer thudding inside his head." Ditto. Now imagine that casual accuracy about beer "thudding" around your head cropping up throughout the massively distended narrative that is Tree of Smoke. There are hundreds of things like this and you never see them coming. I skipped but always had to go back and read properly from exactly the point where I began skimming.

Central to Johnson's dramatised worldview is the belief that it is the mangled and damaged, the downtrodden, who are best placed to achieve - "withstand" is probably a better verb - enlightenment. It's like an inversion of the idea of the law of the jungle where trees vie with each other to reach for the sky, the light. For Johnson the real revelations are at ground level, amid the degradation of mush and swamp. As such there are moments of extreme ugliness and horror. In 1968 a GI spoons out the eye of a VC prisoner and James Houston yells: "Give it to the motherfucker. Make him holler." Thus encouraged the soldier "grabbed the man's eyeballs hanging by the purple optic nerves and turned the red veiny side so the pupils looked back at the empty sockets and the pulp in the cranium. 'Take a good look at yourself, you piece of shit.'" A little while earlier James had emerged from a firefight in the aftermath of which "every blurred young face he looked at gave him back a message of brotherly love." But then his buddy got wounded and ended up in hospital "like the Frankenstein monster laid out in pieces, wired up for the jolt that would wake him to a monster's confused and tortured finish." The book is a monster in that sense, jolted constantly into life by its own damaged circuitry, a mass of spare parts all held together with a relentlessly deranged sense of purpose and quotations from Artaud and Cioran.

Johnson is all over the place and he is an artist of strange diligence. It is as if his skewed relationship to the sentence - not really knowing what one is and yet knowing exactly what to do with it - operates, here, at the level of structure. Tree of Smoke is as excessive and messy as Moby Dick. Anything further removed from the tucked-up, hospital corners school of British fiction is hard to imagine. It's a big, dirty, unmade bed of a book and, once you settle in you're in no hurry to get out.

· Geof Dyer's The Ongoing Moment is published by Abacus. To order Tree of Smoke for £15.99 with free UK p&p call Guardian book service on 0870 836 0875 or go to theguardian.com/bookshop

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