Is Harriet Green the person for whom the phrase 'She never stops' was coined? It's not usually meant to be taken literally, but even among today's notoriously time-pressed CEOs, doomed by globalisation to cover half a dozen time zones at once, she comes closer to actually achieving round-the-clock 'always on' status than just about anyone else you are likely to encounter in the boardrooms of UK plc.
'I don't sleep much, I never have. It's over-rated. The mystery is how my mother went on to have two more children when she already had one like me who just didn't sleep,' says the improbably bright-eyed boss of travel giant Thomas Cook, who gets by on just three or four hours' kip a night, a la Margaret Thatcher.
She bests all her alpha-male oppos who think that 5.30am is a suitably macho time to get up by, rising at the frankly incredible hour of 3.30am.
What on earth does she do before sparrow's fart every morning? Well, for starters: 'I do all my own email. I have a system and I do delegate, of course, but the only person who accesses my main Thomas Cook email address is me.'
She puts aside several hours - mostly at the beginning and the end of the day - to tackle it. 'In every business I've ever run for the past 20 years, I do Ask Harriet on day one. Via email. I get hundreds on any subject you can think of.
'I reply to every email within 24 hours and usually a lot faster. When people realised that, it sent the most symbolic ripple through the organisation. "She replies to us, and quickly, so we've got to keep moving!" It allows me then to say: "We've got to do these things at a pace."'
As if that isn't enough, she has her own busy Twitter account, is a great jotter down of thoughts and observations (as a shelf of battered notebooks in her modest office attests) and a prodigious reader. 'I love books. I love the smell of them and the comfort of reading. I couldn't do my job without reading,' she says.
Her tastes, in case you were wondering, run well beyond the usual business bestsellers, from Sigmund Freud to Donna Tartt and everything in between.
'I've just finished reading an 800-page biography of Nansen. It was quite a trek and he didn't lose anybody,' she says of the oft-overlooked Norwegian polar explorer and Nobel Prize winner who in 1888 made the first crossing of Greenland.
In anyone else, such gratuitous levels of pre-dawn productivity would smack of one-upmanship, but Green's cheerful unorthodoxy is unforced. Not entirely normal, but authentic nonetheless. 'There's nothing clinically proven that says a lack of sleep is bad for you. I am blessed with a lot of time; I have lots of hours and I am always looking for things to do.'
So running Thomas Cook must be her perfect job. By any standards, she has had a crazy number of things to do in the 18 months since she took over the hot seat of the sorely tried travel business in August 2012.
While the nation revelled in the Olympic glories of Mo Farah, Victoria Pendleton, Jessica Ennis and the rest, Green was grappling with a business teetering on the brink of extinction. Only the year before, it had been forced to seek a £200m bailout from its bankers, but its share price was still underwater and investor patience was running short.
It wasn't the only holiday operator to be caught out by the Arab Spring and the ensuing collapse in demand for holidays in Egypt and north Africa. But its failure to keep up with the increasingly adventurous internet-savvy travelling public, for whom a fortnight's all-inclusive package deal on the Costa del Sol no longer cuts the mustard, was less easily explained away.
In 2011, it came last in MT's annual Britain's Most Admired Companies Awards, in 238th place, taking the dubious accolade of Britain's Least Admired Company.
Most pressing of all, it was racing towards a mountain of maturing debt, with no obvious means at hand to scale it. It looked as if the 172-year-old business, founded in 1841 by the eponymous Thomas Cook to ferry fellow Temperance Society members from Market Harborough to Loughborough, might not see its 173rd birthday.
So one of Green's first tasks was to go back to the banks and ask for more dosh - a lot more. 'On the day I joined, the market cap was £146m,' she says. 'And we had to raise £1.6bn quickly - that was going to be very hard to do. Basically, we were running out of money.
'I spent the entire month before I joined Thomas Cook talking to investors, analysts, the press - anyone who could give me an external perspective. Then I did exactly the same within the organisation for the month after I joined.
'The people here were amazingly open - I sent a video blast asking everyone to do a survey and tell me what they thought, and within a month I had 8,000 detailed responses.'
Isn't the thought of being on the receiving end of so much undiluted employee angst a little, well, discouraging? Perish the thought. 'It's vitally important to keep getting better,' she says.
A self-confessed feedback junkie, she treasures a well-thumbed file containing the results of all 22 360-degree appraisals she has undergone over the course of her career. Unlike many, she seems to relish the dreaded process by which everyone who works with you - from staff to customers, boardroom to postroom - gets to say what they really think.
It helps, she says, to keep her grounded. As does her family. 'I get a lot of feedback, especially from my kids. They are the ultimate test of authenticity. You should never believe your own bullshit, especially with your family. If that happens, you're dead.' Unlike Thomas Cook, which she has nursed back to fighting fitness at a speed even Florence Nightingale would have been proud of.
Investors have backed a £305m rights issue and a further £120m has been raised from new shares. Not content with her original target of £400m of savings, £440m (and rising) of costs have been slashed, with the same amount to come again by 2018, she reckons. The share price has soared by an astonishing 950%.
The inevitable 'non-core' assets, totalling £60m, have gone, including the firm's share in air traffic control operation NATS for £38m last autumn. MT columnist Luke Johnson picked up ski operator Neilson for £7m in November.
The branding has also been given a new look - out have gone the familiar red and white logo and 'Don't just book it, Thomas Cook it' slogan, to be replaced by a gold-coloured 'sunny heart' and the words 'Let's Go!'. Bookings for its more upmarket boutique hotels are soaring.
The company may have had the sort of balance sheet that would ruin anyone's holiday, but underneath it all, she says, was a good business trying to get out: '30,000 people in 42 countries, 90-odd planes, £10bn in revenues.
'Obviously, I didn't think it was the job from hell. I'm not suicidal. We had to move at speed and it suits my metabolism to do things that way. I am not risk averse.'
Full-year, pre-tax losses have been halved to £158m and trading has improved substantially - at an operating level Thomas Cook now makes a profit of £263m.
So well received has the revival been that the Thomas Cook turnaround has now joined the esteemed ranks of case studies presented at Harvard Business School.
But, despite the hectic pace of progress, you can't help feeling that she thinks she could have moved even faster. 'I was conscious of showing a lot more patience than I usually do, because the organisation was really quite sick. I spent a lot more time ensuring that people understood not only the what but also the how.'
The changes she has wrought have not been without their human costs, however - some 2,500 employees have gone, many as a result of the closure of around 200 high-street shops. And yet morale - notoriously sensitive to job losses - remains high. Why?
'I don't think you can do this kind of job unless you really like people. From my perspective, it's not about one great product or idea. It's people doing their excellent best, everyday, that produces great companies.
'And at some point, the people here decided that I did have their best interests and the survival of the company as my absolute priority.'
Green has also shifted the group's efforts towards the internet to satisfy the contemporary punter's desire to shop online for holidays, too - an area that Thomas Cook's bosses had let slide for far too long.
Many a head was scratched back in 2011 when the previous management announced its merger with Co-op Travel, creating the largest high-street travel business in the country at precisely the time when common sense suggested that closing shops rather than opening them was the way forward.
It was symptomatic of a business stuck in the past, she says. 'People didn't move in or out of the industry very much, and quite a part of the travel business seemed trapped in a prior age as far as technology and management thinking were concerned. There were lots of myths when I arrived at Thomas Cook; it was an immensely fact-free environment.'
Now, it's all about letting customers do it their way - her target for web-based sales is 50% by 2015, up from around a third when she joined.
Green thinks a good deal about her customers and loves the direct connection of social media. 'We monitor our social media hard - Facebook, Twitter, Instagram, Reddit - I know three times a day what's out there and how that affects us.'
And unlike many a gilded denizen of the boardroom, she is not afraid to roll up her sleeves and get down with the punters. Her Twitter stream is littered with both brickbats and bouquets, but harassed holidaymakers who tweet @harrietgreen1 in exasperation generally receive prompt and practical replies.
To Green, the thoughts of her 3,200 or so followers are feedback gold, of course, all the more valuable because it comes from the horse's mouth. 'I use Twitter because it's a highly effective comms tool and 50% of my customers use it. One of the problems with the upper echelons of anything is that you systematically get rid of people who tell you it like it is.'
She has no such qualms herself. Impish and elegantly turned out in tailored trouser suit, killer shoes and deceptively simple hairdo, she chats animatedly with lots of hand gestures and an intense, interested manner. She's softly spoken and is an engaged listener, but it doesn't take a lot to imagine that being the focus of her laser-beam gaze could become pretty uncomfortable if you ever got caught dropping the ball.
Green lives with her husband, Graham, an engineer, in the leafy academic Oxford suburb of Summertown. Their two children - from her husband's previous marriage - are grown up. The eldest, George, 26, has just left Deloitte to join Octavius Black's corporate development and training business, The MindGym, while her stepdaughter, Gemma, works in social media.
'I try not to give them advice because you know they won't take it. But I do tell them not to be tall and thin.
'You get a lot of tall, thin leaders who have always been the goldenballs - the people who always get the promotion. I say to my children that they should take the roles that make them rounder and richer (not in the material sense), the kind of roles that the goldenballs won't do.
'Because for kids, these days, success is about how you differentiate yourself, and you do that by doing things that aren't normal.'
Growing up in the Cotswolds in the 1960s and 1970s as the eldest of three must at times have been a bit too normal for Green. She attended a state school, Westwood's Grammar, in Gloucestershire and a penchant for am-dram helped add excitement. 'We did a lot of going out and doing tap and ballet and acting.'
It's an experience that's come in handy again recently. 'There have been days over the past year when I've thought, oh great, another bank presentation. But you have to put on your best face and get out there.'
When things look really bad, she says, she either channels Boadicea, legendary warrior queen of the Iceni, or sits down and attempts to achieve a meditative state. 'I do pre-bank yoga,' she says, 'to cleanse my head. It helps me calm down and keep a sense of proportion.
'You can tell everything about a person from their yoga,' she continues. 'Take me. I am eminently flexible, there is no bend or stretch I can't do. But I am not particularly balanced. My husband, on the other hand, isn't so flexible but he is incredibly balanced.
'But I am not really very good at it. My Sivananda guru would say that I have never come close to a meditative state and I don't think I ever will.'
The defining event of her childhood came when her father - who became ill with a brain tumour when she was 11 - died when she was 14. 'That was a formative moment,' she says. 'But I was a pretty strong kid and the message I took from it was: "Shit happens, so you have to pack a lot in and make the most of every day."'
Her business career began by accident. After studying medieval history at King's College London - 'I loved it. I thought historians helped us learn from the past and avoid making the same mistakes' - she thought the only jobs she was qualified for were teaching or the BBC.
Neither floated her boat, but then she saw an ad in a now-defunct magazine called Working Women. 'It appealed for women with integrity and drive who wanted to learn about business,' she says. 'I felt that it had been placed there especially for me.'
It led to a graduate trainee job at distribution outfit Macro Group, where she discovered she liked the cut and thrust of commerce. 'It's easy to measure whether or not you're a success in business. Did you make more money than the last guy? Is the business more valuable? Do people stay with you?'
That led in turn to a stint at Arrow Electronics, where she travelled the world running businesses in northern Europe, South Africa, Asia and China.
The step up to CEO came in 2006, when she joined electronics distribution business Premier Farnell with a remit to shake it up. The move from there to Thomas Cook was now only an email away - albeit an unsolicited one.
She in effect cold-called chairman Frank Meysman, having read of the firm's plight in the media - the kind of tactic that takes plenty of chutzpah but is usually more suited to those trying to get on the bottom rung of the career ladder rather than the top.
He clearly appreciated the direct approach, asked her in for a chat and she landed the biggest job of her career, despite having never met Meysman or worked in the travel game. What pushes her to make such bold moves?
'The person I compete with most is me. I just want to be better and better. When you lose a strong, good parent, you always have in the back of your mind that if you ever meet him again you should be the best person that you can be.'
Money, she says, she is not particularly interested in, despite a basic salary of £680,000 and a potential £1.3m payout if all continues to go swimmingly at Thomas Cook. 'If you are focused on the cause, you will be appropriately rewarded. People are sensitive to greed.'
But that's not to say she doesn't enjoy the spoils, as her holiday home in Thailand - 'I don't think the kids would visit as much if it were in Croydon' - and penchant for designer clobber attest.
'I go into schools to get in front of 13 and 14 year-olds and explain why business is a good thing to do. I tell them I have the best shoes and great outfits that I bought myself, I travel the world and I get to tell people what to do. It's fun!'
Diversity is a touchstone and she is keen that the firm's management should reflect those who buy its products. 'Seventy per cent of our customers are women and 65% of our employees.' And yet, in the bad old days, the bosses were 'a small number of British and German men'.
No longer. Thomas Cook has three women on its board - Green and two non-executives, Dawn Airey (senior Yahoo! executive and former head of Channel Five) and Martine Verluyten, former CFO of mobile operator Mobistar. It also has one less man, since former Co-op chief executive Peter Marks stood down last month in the wake of the scandal that hit his old employer.
Just don't try and persuade her that quotas are the best way of achieving diversity. 'I sit on a number of other boards - heavy-hitters like Emerson, a £25bn global engineering group, and BAE Systems.
'Now, I am no shrinking violet, I don't really give a damn whether people like what I have to say and I am not trying to win any popularity contests. But I can tell you that the first time you speak at the boardroom table of a BAE or an Emerson, you want to know that you are there because of your ability and strength of purpose.
'If there's any reason for anyone around the table to think, why am I taking this person seriously? She is here on someone else's quota - well, I never want to be in that position.'
The way to increase the number of female leaders is to provide more and better role models and support, she says. 'It's about the pipeline. Business is not always perceived to be a good thing to do, and there aren't always the support systems.
'Could I have done what I did last year with two two-year-olds at home? Tougher choices would have to have been made.'
Talking of tough choices, sooner or later she is going to have to decide what to do after dotting the i's and crossing the t's at Thomas Cook. Whatever it is, she won't hang around when the time comes. 'CEOs spend too long in the same job,' she says. 'You should do what you have to do, have maybe a couple of years hugging everyone and then move on. I think that adds up to six or seven years, not 16 or 17.'
She is unlikely to be short of offers, so bid early to avoid disappointment. Emails by 3am, please.
THREE CHALLENGES FACING GREEN
Green in a minute
1961: Born 12 December, Cheltenham, Gloucester. Brought up in nearby Shipton. Educated at Westwood's Grammar and King's College London, where she studies medieval history
1985: Joins Macro Group as management trainee. Managing director by age 29
1994: Arrow Electronics. Various roles, including MD, northern Europe, head of sales, China, and president, Asia Pacific
2006: CEO, Premier Farnell, FTSE 250 electronics distribution business
2012: CEO, Thomas Cook Group