CONSIDERING Irvine Welsh's delight in shocking readers with grotesque passages dredged from the bottom of the human psyche, readers of a more delicate disposition might quiver on hearing that his new novel deals with murder and paedophilia. But Crime is by some distance Welsh's most restrained and thoughtful work, both in terms of its relatively conventional structure and style, and in its moral centre.

In the past Welsh has plundered previous novels for new angles on old characters, and he does so again here. Crime centres around the Edinburgh copper Detective Inspector Ray Lennox, a bit-part character in Welsh's rampaging coke-fuelled rant Filth. The book opens with Lennox on holiday in Miami with his fiancée Trudi, supposedly recovering from a nervous breakdown and planning for his wedding.

The action along the Florida coastline is interspersed with flashbacks to Edinburgh, interestingly delivered in the second person, which reveal the cause of Lennox's current fragile state of mind, the horrific rape and murder of a seven-year-old girl, a case that Lennox eventually solved, but not before it had taken its toll on him.

Lennox is far from mentally recovered. After a bust-up with Trudi, he finds himself on a booze and coke bender, and things quickly get out of hand. A brawl breaks out between Lennox and two unsavoury characters at the apartment of a woman he has been drinking with, the upshot being that Lennox finds himself in sole charge of the woman's ten-year-old daughter, Tianna, a suspected victim of abuse.

In an effort to keep the girl safe, Lennox embarks on a road trip with her across Florida, a tense and unsettling journey, and one that gradually hints at a much more widespread network of organised paedophilia.

Along the way Lennox isn't helped by his own crumbling mind and body, as he starts to go cold turkey from the alcohol, coke and anti-depressants he has been using as emotional crutches. He is also haunted by the memory of the dead Scottish girl, and threatened by Tianna's inappropriately sexual behaviour.

Crime is written in a style unlike most of Welsh's work. There is no stream-of-consciousness Edinburgh slang, despite the author writing firmly from inside Lennox's head. Instead we get a narrative in conventional English, which reduces the visceral immediacy of the prose, but which also allows Welsh to go deeper into his characters, as well as to navigate his plot developments more clearly.

There are elements of genre crime fiction in that plot, but they are nicely subverted. The second-person narrative gives the Edinburgh sections a creepy intimacy, while the edgy mental gymnastics of Lennox on the road trip with the young girl add another layer of brooding uncertainty to proceedings.

Freed from the constrictions of his usual full-on first-person rants, Welsh reveals himself to be good at description, especially of settings and weather. The sweltering heat of Miami and the alien wilderness of the Everglades and the Gulf of Mexico coast are vividly evoked, although these passages are occasionally overwritten.

Perhaps Crime's diversion should not come as a surprise. In his last book, the short story collection If You Liked School, You'll Love Work, Welsh experimented with different styles and backdrops (several stories were set in America), revealing himself to be a more varied writer than previously imagined.

One thing Crime has in common with most of Welsh's work is its big set pieces. There are several explosive scenes that ramp up the tension, most notably an altercation on a yacht in the middle of the Gulf of Mexico that brings to mind the classic final scene of Cape Fear.

But for the most part, Crime does not rely on gruesome shocks. The themes of organised paedophile rings, child abuse and murder are distressing, but Welsh's take is surprisingly considered and compassionate, and ultimately an old-fashioned moral one.

Crime by Irvine Welsh
Cape, £18.99; 320pp Buy the book from Books First £11.69 including free delivery

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