I find it difficult to remember, in retrospect, why I thought it would impress Ranulph Fiennes - a man who has crossed the Antarctic unaided and who sawed the ends off his own, frostbitten fingers - if I arrived to interview him on a bicycle. I could have gone by cab and been waiting calmly in the foyer of the Lanesborough Hotel by 8 a.m. Instead, I pitch up at 8.15 with black particles of diesel exhaust stuck to my puce face.
'Sorry I'm late, I came by bicycle,' I explain to a tall, middle-aged man with a fine-boned, urgent-looking face like a pencil sketch. Sir Ranulph Twisleton-Wykeham-Fiennes, Bt, OBE stares at me with a polite but total lack of interest.
As we sit across the breakfast table from each other, previous articles about him suddenly make sense. 'Not an easy interview,' said the Guardian last year. 'Strangely passionless,' said Scotland on Sunday. 'Like stirring the void with a teaspoon,' concluded Anthony Clare after interrogating him for In the Psychiatrist's Chair. If people who are eager to please are very present in their eyes, Fiennes is looking at me from the other end of a mile-long tunnel. He has admitted to treating interviews as a game in which he must not reveal too much. He has the unfair advantage of SAS training.
One subject during the course of our conversation brings him out of his tunnel: Scott of the Antarctic. This year Fiennes has devoted himself to writing a biography that will overturn the 20-year orthodoxy that Captain Scott was a failure. The polar historian Roland Huntford, in his Scott and Amundsen of 1979, was the first to present Scott as an anti-hero. He calls him 'stupid' and 'recklessly incompetent', 'a monument to sheer ambition and bull-headed persistence'. It is now received wisdom that, far from being a model of British fortitude and valour, Scott was a bully who endangered his men's lives by relying on old-fashioned methods for the sake of his vanity.
This is the aspect of modern Britain that Fiennes most loathes: its appetite for denigrating heroes. 'Cynicism started pulling away at our standards as early as the 1920s,' he says, leaning forward. 'I'm talking about people like Scott or Lawrence of Arabia, Florence Nightingale and Winston Churchill, or, very recently, Laurens van der Post. All these big names have had a biographer who has managed to become well off on the proceeds of attacking them. There is now a voracious public waiting for the next person to topple from their pedestal. The readership for this is far greater than for an honest, balanced critique.'
A whippety French waiter asks for our order. 'I'll have the almond whorffle,' says Sir Ranulph, pronouncing his breakfast as befits a man who can trace his ancestry back to Charlemagne. 'Whiffle,' corrects the waiter.
It is part of Fiennes's oddness and charm that he can't quite believe that money or acclaim might be enough to motivate someone to write an unfair account. Of the biographer J.D.F. Jones, who recently made great hay with Laurens van der Post's affair with his 14-year-old ward, he asked, 'So what do you think made him do that? Do you think he had a personal grudge against van der Post? Or do you think he started with an open mind and genuinely thought that this is what the man was like?' Fiennes has the ability, unique among former SAS members and psychopaths, of being able to look one straight in the eye for an indefinite period of time.
The whorffle arrives covered in ice-cream, raisins and maple syrup, and saves me from having to justify prurience. Instead, I ask why, as Scott's reputation has plummeted, his rival and fellow explorer Ernest Shackleton has become an international icon. In a recent list of Britain's 100 greatest people, Shackleton came 11th, just below Shakespeare; Robert Falcon Scott came 54th.
'In the 1980s the media pushed a certain image of Ernest Shackleton as a romantic buccaneer,' says Fiennes. 'This went down very well with Americans who enjoyed idolising a rival to the British Establishment figure of Scott. As for Scott, Huntford has translated his actions into a story that is intensely inaccurate to anyone who has done the same thing. Unfortunately, only a tiny percentage of his readers had had Antarctic manhauling experience, so they were unable to appreciate the false picture he painted, and this has endured.'
Lack of experience is not a charge that anyone could level at Fiennes. After he left Eton, his ambition was to follow his father's lead and command the Royal Scots Greys, but he was unable to pass A-levels in French and German and so could not go to Sandhurst. 'I kept thinking they would change the rules [about A-levels],' he once said. 'But there's no point crying over spilt milk.' That should be his epitaph.
A stint in the SAS ended after he used gelignite and detonators to try to blow up the film set of Dr Dolittle in Castle Combe (for ethical reasons), and he and his wife Ginny set up as expedition leaders. Since then, Fiennes has completed the world's first surface journey around the polar axis, broken the record for the furthest north unsupported north polar expedition, discovered Ptolemy's long-lost Atlantis of the sands, and led the first unsupported crossing of the Antarctic continent - the longest unsupported polar journey in history.
'If you look at the facts about Scott and Shackleton properly, it becomes much less clear who failed and who succeeded,' explains Fiennes. 'Shackleton sent a ship from Australia to drop food off from the Pole to the far coast in preparation for his crossing.' Here Fiennes positions the marmalade to represent the Pole and tracks Shackleton's route across the tablecloth with his right forefinger. He keeps his injured left hand in the pocket of his green, tweed coat. 'But the men were incredibly badly organised by Shackleton, and at least three of them were killed during the expedition. We don't hear about that because it doesn't fit the current agenda.'
'Gosh,' I say. 'I hadn't read that.'
'You're exactly like Roland Huntford, then!' says Fiennes, excitedly. I am a little taken aback. 'Sorry,' he says. 'I'm not being rude; it's just that he doesn't know anything either. He has never done any polar expeditions. He just interprets things as he pleases.'
'Is there any truth at all, then, to Huntford's descriptions of the antipathy between members of Scott's last expedition?' I ask.
'Well, Dr Wilson was the strongest personality,' says Fiennes, settling into a familiar theme. 'Very Christian and very honest. His university and school contemporaries all testify to that. Wilson wrote extensive diaries, often critical, and if he had felt that way about Scott he certainly wouldn't have written what he did, which was virtually all praise. Scott was a very perspicacious, philosophical, sharp-minded man. Far from being vain, he was full of self-doubt. He had natural weaknesses that he had to overcome to do the amazing things he did, using the British method.'
Ah, the 'British method': another of Huntford's charges. Huntford attributes to vanity Scott's decision to use manpower without sledge-dogs. 'Surely he's right here. Walking can't be the best way to cross Antarctica?'
'It is easy now to criticise Scott's decision not to use dogs, but at the time his point of view was logical. Give me ten minutes and I could tell you why,' says Fiennes. 'If you're travelling to the North Pole through broken sea ice, both now and back in Scott's day, the best method is to haul your own load. And that was the sort of ice that the Brits were used to. On the flat ice in Antarctica dogs come into their own, but remember that Scott's first expedition was ten years earlier than Amundsen's. Back then, in 1901, his men were the first to travel any distance over Antarctica. They didn't know what sort of terrain to expect, so they naturally planned to use human power.
'As it turned out, Antarctica is far more suitable th an most places for dogs, but you still have to have dumps of dog food everywhere. If, for instance, you tried to cross the whole of Antarctica with dogs, and no dumps, you couldn't - a fact proved by the expedition that I did with Mike Stroud in the 1990s.'
I think I understand from this that Scott was very nearly right to go on foot, and that it was, at any rate, a pragmatic rather than a selfish decision. I try out a more personal question. 'Have you ever wished that you'd lived 100 years ago, in the age of pioneer polar exploration?'
'No, not really.' Fiennes immediately adopts the deadpan tone of voice he uses to deal with questions about himself.
'Did you think about Scott when you were huddled in a tent in the Antarctic?'
'No, not really. We didn't read any books about the early expeditions before we did our crossing in the 1980s, because we didn't think it applicable to us.'
I know that Fiennes feels personally attached enough to Scott to have bought at auction a biscuit that was found next to his body for £3,910, but he won't be drawn into sentiment. I also know that, although he once admitted to being motivated by a desire to impress his distinguished, long-dead father, if I ask him now, he will tell me that he explores to pay his bills.
Fiennes's talent for stifling enthusiasm is as impressive as his ability to inspire it, so we return to Scott's reputation, and a once more animated Fiennes explains the urgency of changing history before it is too late.
'The Last Place on Earth, a film based entirely on Huntford's book, gets shown to this day to any explorer or scientist who goes to the South Pole,' he says. 'They arrive all tender and receptive at the Scott/Amundsen base and get indoctrinated through the medium of Roland Huntford's hideously biased portrait of Scott. They then go back to US universities as polar experts because they've spent time at the Pole, and regurgitate Huntford's view of Scott as vain, selfish and unsuccessful. Future Antarctic