Inherent Vice, By Thomas Pynchon

There's some problem the British have with Thomas Pynchon. Of those who've heard of him, few have read him, and of those who've read him, even fewer seem able to metabolise him. When his last novel, Against the Day, was published in 2006, weighing in at an eye- watering 1,100 pages, I remember a presenter of The Today Programme taking an almost personal offence, doubting aloud whether anyone actually read this sort of thing. She stoutly added that no one she knew had been able to finish Gravity's Rainbow, Pynchon's 1973 winner of the US National Book Award. And if all the friends of a Radio 4 presenter can't stomach something, well! The problem was hardly likely to lie with them.

Across the Atlantic, by contrast: widely recognised as one of America's most important writers ever, Pynchon is also the recipient of a MacArthur "Genius" Award and a controversially overruled Pulitzer; he's been America's best chance for the Nobel for a decade now, and, probably most significantly, a two-time guest star on The Simpsons. So, even before we get to the text, we have a huge and not necessarily soluble puzzle.

Which is appropriate. Inherent Vice is ostensibly a hard-boiled mystery, set in 1971 Los Angeles and Las Vegas, following the adventures of dope-fiend and private investigator Larry "Doc" Sportello. Doc's ex-girlfriend turns up out of the blue and hires him to investigate a plot to kidnap her new billionaire boyfriend, the notorious property developer Mickey Wolfmann, supposedly cooked up by Wolfmann's wife and her lover. Doc is, naturally, still in love with his ex, although he's currently seeing a junior district attorney, so his motivation is as complex as hell – as is the plot already, and we're not quite at the bottom of page two.

So far, so noir. We take in bent and straight cops, mysterious knockings-out, hookers with hearts of gold, corruption in the DA's office and conspiracies up to the highest levels of government. From that point of view, it's a rare display of genre discipline from Pynchon, and we never stray too far from the central quest into the mystery of Wolfmann's disappearance. Like in Roman Polanski's Chinatown, our hero appears in every scene, and indeed, Inherent Vice is reminiscent of that archetypal neo-noir in both darkness and subject matter.

But 1971 is also the year of Hunter S Thompson's most famous drugs binge and rare is the page without a joint, tab, stash, roach clip, bag of junk, trip or weed-fuelled sex. Everyone has an amazing, indeed numbing, amount of sex, reinforcing the sense of anomie and permanent bummer, which would imbalance any less saturated story. But that's just another of Pynchon's talents: to write several books simultaneously. Because, for all its darkness – Nixon and Kissinger shimmer like evil spirits just beyond sight – the novel is more or less continuously comic, stuffed with one- liners and addled doper humour: "Come on, Sportello, you know we'll be more than happy to give you a lift. Watch your head."

"Watch my... How'm I spoze to do that, man?"

Pynchon is both the US's most serious and most funny writer. With his most accessible book to date – half Chinatown, half Fear and Loathing, all searing jeremiad about the modern American soul – he may have come up with something even the British literati can read.

Thomas Leveritt's novel 'The Exchange-Rate Between Love & Money' is published by Vintage