Irvine Welsh's one-word titles - we've already had Ecstasy, Filth, Glue and Porno - are like advertising slogans, strong on suggestion but weak on meaning. His latest novel could as easily be called Sex; it contains scenes of remembered sex, fantasised sex, failed sex, oral sex (both voluntary and involuntary), paid-for sex, adulterous sex, filmed sex, cruel sex, underage sex and other assorted activities everyone knows we do to please and harm our bodies and minds. This being Welsh's world, the book also features lots of swearing and drugs, and a dead cat crawling with maggots.

The reference to Raskolnikov on page 278 isn't enough to establish that the book belongs with Dostoevsky. It's more a television thriller, translated awkwardly to the page. Ray Lennox is a depressed Scottish detective, taking a trip to Florida with his fiancée, Trudi. Their holiday is interrupted by Ray's urge to protect a little girl abandoned by her junkie mother and now at the mercy of a fiendish gang of paedophiles. There's a lot of driving through swamps, avoiding alligators, heading on boats out to sea and back, racing against the clock, threatening people with guns and - whenever the plot falters - snorting cocaine.

Welsh tries diligently to muster his fictional devices, such as switching narrative pronouns from “he” to “you” as Ray's bewildered mind is seen from different angles, but the overall effect is one of lumbering improbability. There are frequent flashbacks to scenes that obsess him (a murdered child's body, his own boyhood degradation by a child molester, family quarrels) but duplication dulls rather than sharpens the effect. Contrasting motifs - Trudi's preoccupation with glossy bridal magazines, Ray's with his wobbly libido - are developed without grace or subtlety. The same overwrought style conveys everyone's sensations and thoughts.

The writing strives for extremes, but relentlessly fails to achieve more than the banal. Injustice “sowed a sickening moral relativism into your psyche”, a poster of the murdered child's eyes “blitzed into the psyche of the British public”, Ray's moments of panic “sting his psyche like a bad curry would his gullet”. Elsewhere, a “dark mood creeps through his veins like a poison”; as Trudi gets angry, she “feels the poison flow through her”; and a paedophile is “transformed by a black venom seeping through his veins”. Ray's “piano-wire nerves” are stretched to their limit; 70 pages later “his nerves are now like piano wire”.

We are helpfully told that America is “more than a country of big cars and strange sports”, but the supporting evidence seems to have been borrowed from an offensively trite travelogue. Looking at black people on the bus, Ray notes that “their bodies move to a different rhythm”; another district is “full of black youths glowering in brooding menace from street corners”. Giant cranes stand over downtown Miami - you've guessed it - “like monstrous birds of prey”. Copywriters are also drawn on for their contribution: when Ray drinks a glass of orange juice, “the Florida sunshine explodes in his taste buds”.

It is hard to be interested in what foul-mouthed or inarticulate characters have to say. Welsh's solution is to put his own prose on stilts, but it frequently collapses. When Ray talks to a crack whore, “falsehoods pirouette from his mouth”; soon he is trapped “in a skanky vortex of his own making”; refusing to be masturbated by a lap-dancer is “less a self-esteem issue than a professional pride one”; his 35th birthday “delivered a quantum leap into middle age”. Within three pages, a car-rental clerk is described as “chronically overweight”, “corpulent” and “obese” [twice]. Readable novels can't be built out of repetitious clichés.

The final offence is the pervasive sentimentality. There are many pages on Scottish football, talking of how “the glory days” at Hearts aren't coming back now that “foreign mercenaries” have replaced “local lads”, and how the crowd expresses a deep “communion with nothing less than the beauty and terror of life itself”. This might be pardoned as commonplace claptrap. But to identify the hunt for paedophiles as the essential “battle between good and evil” and Nazi killers as “a giant child-abuse ring” is something more. Such crassly righteous moral confusion belongs in a tabloid editorial rather than in a novel for grown-ups.

Crime by Irvine Welsh
Cape £12.99 pp352

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