Ian Rankin is not so much anti-fashion as non-fashion. Dressed in a washed-out polo shirt and jeans that could have come from a pound shop, he looks more like a bloke standing at the back of a gig than the millionaire creator of hard-drinking, harder-smoking Edinburgh detective John Rebus. When it comes to his books, he will not be following the latest trend either. Unlike rivals, including Reginald Hill, he will not bump off his star in his next and final outing.
Rankin will start writing the final book in the Rebus series in two weeks' time, once he's finished promoting The Naming of the Dead, which came out last week. "Rebus isn't going to die," he says leaning towards me, adding conspiratorially: "I say it will be the final Rebus book, but I have promised my publisher that I will do at least one book with Siobhan [Clarke, Rebus's English sergeant], with him in the background."
Fans will be relieved. Though not everything will go their way. Rebus and Clarke will not end years of sexual tension, broken only by a cringe-making attempted kiss at the end of A Question of Blood. "They will never jump into bed together," the 46-year-old writer says emphatically.
The reason, I suspect, that Rankin can't kill off Rebus is that the character is too deeply embedded in his own psyche. The lives of the two elide. They share the same musical obsessions - during the interview the soft tones of the Scottish band Saint Jude's Infirmary, for whom Rankin has written lyrics, play in the background. And then there's those clothes: Rankin likes bloke anti-chic rather than the all-black numbers worn by the actor Ken Stott in the new Rebus series. Indeed Rankin's only criticism of the programmes is, "Rebus just wouldn't wear that."
The line between reality and fiction thins even more in his latest book, his best in years, which covers the week of the G8 summit last year, kicking off with the march in Edinburgh and Live8 and finishing with a world in shock after the 7/7 bombings. Even George Bush appears - Rebus, it transpires, was responsible for his tumble from a bike in Gleneagles.
The Naming of the Dead is the third overtly political book in the series. The last two tackled immigration, asylum seekers and racism. By focusing on the G8 protests and the Make Poverty History campaign, the book tackles the question of whether the individual can effect change. The conclusion is not optimistic. As protesters take to the streets of Edinburgh and surround Gleneagles, it becomes apparent to Rebus that the decisions they wish to influence have already been made. Worse, he discovers that instead of tackling poverty, aid is tied to arms and, yet again, big business triumphs over the needs of the poor.
Rankin says he used the characters in the book to explore issues raised by the G8 summit so that he could come to his own conclusions. "The concert in Hyde Park, Geldof and Bono on the telly - did any of it make any difference whatsoever?" he asks. Geldof had wanted a million protesters to head north after Live8. "People went to the gig and went home," Rankin observes sourly. Not that he regrets the apathy of London music fans. He thought the whole idea was preposterous. "A million people in Edinburgh would have been a complete nightmare. This idea that we were going to open up our spare rooms and gardens for them was ludicrous. Edinburgh people just wouldn't have done it."
Rankin hopes The Naming of the Dead will help to redress the balance, drawing attention back to the issues instead of the partying of Live8. He hopes it will change opinions. After Fleshmarket Close, which contained a veiled portrait of the Dungavel detention centre and the appalling conditions in which asylum seekers' children were living, the authorities stopped children being kept there.
His willingness to write graphically about places like Dungavel does not extend to the violence at the heart of his books. Unlike rivals such as Patricia Cornwell, Karin Slaughter and Mo Hayder, he does not salivate over every drop of blood. "The people writing the most graphic violence today are women," he says when I ask what he thinks of them. "If you turn that off," he looks nervously at my tape recorder, but continues regardless, going public about one of the great unsaids among crime writers, "I will tell you that they are mostly lesbians as well, which I find interesting." He refuses to go into more detail.
When I recall one book in which a woman was brutally raped and murdered, he flinches. "Most male crime writers I know would flinch morally from over-describing an act of violence against a woman, a rape, murder or whatever." Would he ban it? "When they did a study of killers in the States, they found the books they had all read were the Bible and Catcher in the Rye." His voice drips sarcasm. "Should we ban them? No."
Such sensitivity has not stopped Rebus taking a beating, and Rankin admits that he uses his alter ego to work through his own angst. "I have used him as a punch bag. Any shit that happens in my life, he can deal with it." He looks vaguely ashamed, as if abusing a friend. Leaning forward in his chair, he stares at his feet, hands clasped for comfort. He recalls the discovery that his son Kit, 12, had the neurological disorder Angelman syndrome. He was writing Black and Blue at the time.
"Kit was diagnosed with having severe learning difficulties, or whatever the PC term is for it," he almost spits the words out with contempt. "I would go home from hospital every day and try and write this book. I really put Rebus through the wringer emotionally. There is one scene where he has a fight with his best friend in the dead of night and he is down on his knees, with snot coming out of his nose, crying, full of rage, fear and frustration. That was me, not physically, but emotionally." In the next book Rebus's daughter is in a wheelchair. Rankin had just learned that Kit would not be able to walk. "That was a really despicable thing to do," he says, once more blurring fiction and reality. "I thought, if it is going to happen to me, it is going to happen to you."
Comments like that make it easy to understand why he will miss Rebus. Creatively, there is a "big yawning chasm of nothingness" beyond him, he claims, though he has announced plans for a series of comic books for DC Comic's Hellblazer detective series. It will mark a dream fulfilled: the nine-year-old Rankin gave up creating comics when he realised he couldn't draw. He hasn't stopped reading them. A literary novel is also expected to follow the final Rebus, a chance to prove he can write outside the genre - Rankin has been a vocal critic of the literary establishment's exclusion of genre writers. As well as writing lyrics for Saint Jude's Infirmary, he appears as the singing butler in a pastiche of the Jack Vettriano painting of that name in the band's latest video.
Rankin may miss Rebus, but it will not stop him enjoying himself. The curmudgeonly detective has been Rankin's ticket to the life he wanted when he was growing up in the tough mining town of Cardenden. "By mentioning so much music in the books I have got to meet a lot of musicians," he enthuses, and regales me with a tale of his appearance at the Q Music Awards last year, where he met Nick Cave, Sparks, Ian McCulloch and Jimmy Page. He reels off a litany of names. "Jimmy Page!" His eyes almost pop out of their sockets. Rebus would be impressed.
Biography: Secret poems to global success
Born 28 April 1960 in Cardenden, Fife, Ian Rankin wrote in secret as a child. He was "outed" as a poet to his father James, who worked at Rosyth docks, and mother Isobel when he won a competition in the local paper. He published his first novel, The Flood, in 1986 while working on a PhD at Edinburgh University. He found success in 1987 with Knots and Crosses, about Edinburgh detective John Rebus. Twenty Rebus novels later, he has sold more than six million books worldwide. He lives in Edinburgh with wife Miranda and two teenage sons, Jack and Kit.
'The Naming of the Dead' is published by Orion (£17.99)