A heavy mist is descending as I approach what I hope is the right house, a modernist eyrie surrounded by young pines on a hillside above Oslo. I’m about to ask a man tidying up the basement garage for directions when I recognise him as Henrik Carlsen, a trim, balding, middle-aged engineer in metal-framed glasses. We have met before, 11 years ago, when I came to Norway to interview his son Magnus, then aged 13.

The reason? Magnus had become the youngest grandmaster in the world, The Washington Post had duly dubbed him ‘the Mozart of chess’, and none other than Garry Kasparov had predicted that one day this Norwegian wunderkind would become a world champion. Most prescient the Russian grandmaster proved to be.

Playing against Viswanathan Anand in November 2014 Credit: AP

At 19 Magnus Carlsen became the youngest-ever world number one. At 21 he became the strongest chess player in history, beating Kasparov’s own ‘ratings’ record (ratings are the eye-wateringly complicated way in which relative chess strength is calculated). And at 22 he did indeed become world champion. That was in 2013. He successfully defended his title last year and will mount another defence of it next year. Before that he will be playing in the London Chess Classic, which begins on December 4.

‘On a clear day you can see down to the fjords,’ Henrik says as he emerges from the garage, wiping his hands on his jeans. ‘But you’ll have to take my word for that.’ He and his wife helped their son find this house a few months ago and are house-sitting until he moves in. ‘It was the first one Magnus looked at and he wanted it straight away, which rather ruined our negotiation tactics. He’s like that, impulsive.’ He checks his watch. ‘He’s also always late.’ I notice a sleek new Tesla sports car in the garage. ‘Not mine, sadly,’ Henrik says. ‘It’s Magnus’s company car. Now all he has to do is get round to taking a driving test.’

This throwaway comment is a reminder that Magnus Carlsen is not your typical chess player. In the past decade he has gone from being a prodigy to a superstar, one who has earned millions in sponsorship and prize money, won modelling contracts and was even named by Cosmopolitan magazine as one of the ‘sexiest men of 2013’.

Carlsen rests during a match in 2014 Credit: AP

As Henrik shows me into a sitting room with red sofas and matching abstract paintings, he recalls our earlier encounter in 2004. ‘My wife and I were nervous about agreeing to it,’ he says, ‘because Magnus had never done a press interview before and we didn’t want it to go to his head. We wanted to give him as normal a childhood as possible.’

They were the opposite of pushy parents. It was Magnus who did the pushing. From the age of five, he was able to perform impressive feats of memory, reciting complex geographical facts and figures for fun. His father, himself a keen amateur chess player, took note and taught him how to play. But Magnus showed no interest in this most cerebral of sports until he was eight, when, in a spirit of sibling rivalry, he beat his older sister. He beat his father soon after that, then started to devour books on chess.

His parents decided to take him and his sisters (one older, two younger) out of school for a year, becoming their teachers as they travelled the world playing in chess tournaments. His sisters are students now, one studying medicine, another dance, the third computer engineering. Magnus decided not to go to university, against his parents’ wishes. ‘He’s very wilful,’ his father says now.

Carlsen with his father, Henrik, in 2007 Credit: AFP/Getty

A car pulls up. It is Magnus with his manager. When he enters wearing jeans and a hoody, he overrules his father’s suggestion that we do the interview in the sitting room while he has his lunch in the kitchen. ‘See what I mean?’ Henrik whispers as I relocate to the kitchen and he collects his lunch to eat in the sitting room.

‘My parents are living here at the moment,’ Magnus says in a resonant voice, laced with a faint Norwegian accent. ‘When they least expect it, I will throw them out on the streets.’ He gives a slow-burn, lopsided smile, to show he is joking.

His chestnut hair is teased up into a Justin Bieber quiff, but his slightly simian jaw and brow, along with his full, sulky lips, make Matt Damon a better comparison. For a while he was the moody face of G-Star Raw, the designer clothing brand, along with Liv Tyler and Lily Cole. But he tells me he has given up modelling now. Was it proving a distraction? ‘Um, not really, I just figured out I enjoy playing chess more.’

Playing Gary Kasparov in 2004 Credit: Camera Press

I ask how he can bear not having a licence to drive that lovely new car downstairs. ‘I suppose I should take lessons,’ he says with a shrug. ‘But the main hurdle is the theory test. I’m put off by that.’ Another grin, one that brings us to a psychological paradox. For someone who exhibits phenomenal powers of concentration at the chessboard – he is capable of calculating ‘lines’ that are 30 to 40 moves ahead – Magnus Carlsen is easily bored, and though he is something of a fitness fanatic, as well as being a keen footballer and skier, he is actually quite lazy. He told me so himself last time I met him, which was shortly before the world championship in 2013. ‘Not too much has changed since then,’ he says now. ‘I lie in bed until slightly before lunchtime. But it depends on whose definition of lunchtime it is.’

His laid-back approach extends to his training. He has a full-time coach, the Danish grandmaster Peter Heine Nielsen, but he is not keen on using computers, and in the past he has spent much less time than other elite players preparing his ‘openings’ (an opening is a recognised sequence of initial moves). He has tended to rely instead on instinct, making moves that feel right. It is known as ‘playing with the hand’ and is associated more with ‘speed chess’ (played over as little as a minute or two) than with the much slower ‘classical’ (played under time controls of between 60 and 180 minutes per player). ‘Actually I do much less of that,’ he says, correcting my assumption, ‘because when I play by hand nowadays I seem to make more blunders. I analyse positions much more than I did.’

Another thing he said last time we met was that once he had the world championships out of the way he would have more time for relationships. Has that proved to be the case? ‘No. It hasn’t. I have time to go out and have fun when I’m at home. But I haven’t come very far in terms of settling down and starting a family.’ Has he ever been in love? ‘I don’t think so. I’ve been infatuated, of course, but not in love. No.’

Part of the problem is that he spends half the year travelling, and when he is at home in Oslo and goes out on the town he tends to get mobbed by female fans. ‘It’s a curse and a blessing,’ he shrugs. He is not trying to be cool about it, more matter-of-fact.

He may have put the modelling on hold but ‘Brand Carlsen’ does have other revenue streams, such as his app Play Magnus, which allows you to try your luck against Magnuses of different ages. And he keeps his various sponsors happy by agreeing to stunts, such as beating 10 strong players in simultaneous games, while blindfolded. He seems to enjoy doing them and says he wants to take on 20 players next time.

He has a photographic memory, presumably? ‘I can picture the board, but most top players can do that. I don’t think my memory is exceptional. It is much worse than when I was little. Now I can’t even remember the games I played two months ago.’ Really? The kinked smile again. ‘OK, that’s not true.’

With Liv Tyler in 2011, during New York Fashion Week Credit: Reuters

His love life may not have improved, but in other ways he has changed. He makes good eye contact now. And he seems less arrogant. When I ask him whether he has to, as it were, play against himself, beat his own records to keep motivated, he sighs. ‘Maybe it was like that for a little while but recently I have been playing so poorly that I have to start comparing myself to the others again.’

All great champions, from Muhammad Ali to Roger Federer, need great opponents to reach their potential. Are the former chess world champions Vishy Anand and Vladimir Kramnik his Joe Frazier and Rafael Nadal? ‘Up to a point. But the last few years for me have been like Federer’s first few years at the top, when he didn’t really have an opponent. And I think we’ve yet to see someone make the jump from a steady 2,800 guy [only the top grandmasters have ratings this high; Carlsen’s peak was 2,882] to challenging me and being right there in every tournament. Although I haven’t been playing brilliantly lately, I’m still keeping a substantial lead in the ratings.’

That may sound boastful, but it’s not delivered in that way. He is merely stating facts again. And he does admit that he has his eye on Wei Yi, a 16-year-old Chinese player currently ranked number 25 in the world, who might one day take his crown.

Carlsen at home near Oslo Credit: Adrea Gjestvang

He has always been interested in the history of chess and has had the chance to play both Karpov and Kasparov, two legends of the game. But if he could play anyone in history who would it be? ‘I think the top ones would be Fischer and Capablanca, maybe Mikhail Tal, but I think I would beat Tal pretty easily. Fischer would be more difficult, but I think I could beat him too.’

The American Bobby Fischer famously misplaced his marbles, driven mad by chess, to the point that he had his teeth fillings removed, apparently because he thought the CIA, or possibly the KGB, was sending him radio signals through them. But Carlsen seems to have none of Fischer’s mental instabilities, even if he did once say it was ‘obvious’ he was on the autistic spectrum, and then had to explain it was a joke.

As well as being known as an intuitive player, Carlsen also has a reputation for appearing to be relaxed at the board. He will sometimes get up during a game and wander around, lost in his thoughts. His opponents find it unnerving, which is perhaps no bad thing because, as Fischer once said, ‘the object of chess is to crush the other man’s mind’. On the subject of intimidation, Carlsen, along with Kasparov – who was his coach briefly in 2009 – is the most renowned living chess player in the world, and no doubt some of his opponents are envious of all the attention he gets. Does he think it is an advantage or a disadvantage? ‘I think it’s a huge advantage. My opponents are inevitably a little more timid when they play me. Now I just need to reassert myself and get back to a level of play that justifies their attitude.’

His secret weapon seems to be his three sisters, who often come along to tournaments to support him, and keep his feet on the ground by teasing him. As for a hinterland, he says he doesn’t really listen to classical music – ‘Not listen listen’ – and that, contrary to rumour, he was never that into rap music. ‘I’m not as cool as that.’ He says he doesn’t watch much television. ‘I used to binge-watch TV shows and play PlayStation, but not any more.’ He doesn’t read novels much either, because he finds his concentration goes. ‘For two minutes I will be reading, then I’ll realise I have been thinking about chess and I have to go back and re-read what I just read.’

Football is his biggest passion away from the chessboard and he is a dedicated fan of Real Madrid (last year he took the honorary kick-off before the team’s match against Celta Vigo). For his own amateur side in Oslo he plays in defence, ‘where I can do least damage. I enjoy the camaraderie in the team but prefer kicking around with friends rather than playing organised matches,’ he says. His friends being? ‘Some I know from football, some school, some random. Most of them are chess players.’ Grin. ‘Inevitably.’

When I first met Carlsen, he told me he enjoyed reading Donald Duck comics, which seemed unusual for a 13-year-old. And I have heard that he still enjoys playing on children’s climbing frames. It makes me wonder whether he grew up too quickly. ‘It’s true that I had to behave like an adult whenever I was at chess tournaments,’ he says. ‘Then at home I would overcompensate by being extremely childish. Thus I haven’t really come so far in my development and I am still immature at home. So it’s all gone wrong!’

I ask him to give me an example of this arrested development. ‘I have a very childish sense of humour; I will do a prank and my friends will shake their heads.’ Has he been through a rebellious phase? ‘I’ve tried to grow a beard several times but haven’t managed at all. As for tattoos and piercings, I have a little too much self-respect to do those things.’

At the World Chess Championship last year Credit: EPA

Are there days when he looks at a chessboard and feels sick at the very sight of it? ‘Yes, and on those days I find it helps to play rapid or blitz chess. Sometimes during tournaments I will think, “This is so boring,” and I will have a break and log on to the internet and play a couple of blitz games somewhere anonymously, to have a bit of fun. The cheap thrill for me is tricking some guy into a one-minute game. It helps me get back on track.’

Although there is a photograph of him laughing after jumping in a swimming pool in his dinner jacket, taken a few hours after he became world champion, he doesn’t seem an excitable person generally. Quite unemotional, in fact. Did becoming champion make him happy? ‘I think getting to number one meant more to me. I guess my thoughts about becoming world champion were that it would be a bigger deal if I hadn’t won it.’

At this point I feel as if the fog outside has crept inside. He’s an inscrutable young man is Magnus Carlsen, one defined by his contradictions. But I get the impression that, at 24, he is maturing and has started taking his chess more seriously, which must be worrying for his opponents. That said, despite his freakish memory and his cold brilliance at the chessboard, he still manages to seem normal. I say as much to his father when the interview ends and Magnus goes off to do the photographs. ‘Thank you,’ Henrik says in his earnest, softly spoken way. ‘In our family we appreciate results, but they are not the most important thing.’

The 7th London Chess Classic takes place between 4-13th December