Covered in blood and carrying a stranger in his arms, Ed Davey turned to see the lights of a high-speed train hurtling towards him. A split-second decision to help a woman in trouble late one December night was about to cost him his life. "I decided that I had to go across the live rails to the other side," the mild-mannered Liberal Democrat says, matter of factly.
The new Secretary of State for Energy and Climate Change, in his first interview since his "exhilarating" promotion, recalls in precise detail the dramatic moment he saved a woman's life, repeatedly insisting that it was out of character.
"It was in December 1994. I was on platform 11 at Clapham Junction waiting to get my train home. It was about 10 o'clock at night, and a train came through and stopped at platform 12. This lady was bundled out of a door and a gentleman came out shouting after her. He pushed her down on to the platform and got on to the train. She tried to get on the train as it was pulling out, and fell between the train and the platform. Everyone went 'ooh... ahhh... gosh', but didn't seem to be doing anything."
And so, days before his 29th birthday, he calmly crossed the platform, took his coat off – "I was concerned that if I went down there it could get caught, and there were the electric lines" – and jumped down on to a line at Britain's busiest train station.
"She hadn't gone on to the live line, but she wasn't moving. There weren't any limbs lost, but she didn't look very good." As he checked to see if she was still breathing, the worst happened. "I was wondering whether to move her or not, and I looked up. It was late at night and there were these two big lights coming my way."
He quickly picked the woman up, but then faced a choice. If he'd lifted her on to the platform from which she had fallen, "I'd have been on the track and I'd have been killed". So he made his decision and "gingerly stepped across the live rails" and lifted her on to the platform opposite. "By the time I had got to the side, the train had stopped about three or four yards from where we were. I had blood from her all over me.
The police arrived. "I got up and was shaking rather a lot. They gave me a cup of tea, they took my name and I just went home." Six months later he received a Royal Humane Society bravery award and a Chief Constable's Commendation from the British Transport Police. "I never heard from the lady."
Even his new aides are left stunned by the story. In truth, the softly spoken, father of one could not be a less likely hero. "Do I go around waiting to do the superhero bit? No, I don't. I haven't done anything like it before or since." He insists many people would have done the same, and it's the armed forces and emergency services who "every day put their lives on the line" who are the truly "courageous people".
Born on Christmas Day 1965, Mr Davey has had more than his fair share of tragedy. His father, John Davey, died when Ed was just five. Later his mother, Nina, was diagnosed with secondary bone cancer. Mr Davey nursed her for three years before she died when he was 15. "My grandfather was like a father figure to me."
He has few recollections of his father, whose family had been miners in Nottinghamshire. Mr Davey Sr had made "a lot of money" as a local solicitor and left provision for his three sons to be privately educated at the prestigious Nottingham High School. "He was obviously a very careful man," Mr Davey says. "When some families lose their father they are financially seriously hit. But while we weren't wealthy – far from it – we were not poor. The real blow for me was when my mother became ill."
The younger Davey sons nursed her at home. "She was a very determined lady, a very strong lady. That was quite difficult, but it made you resilient. It made you stronger."
After his mother died, he lived in turn with each of his brothers and later his grandparents. School provided "stability" at a difficult time. He became head boy, and was a contemporary of the Shadow Chancellor. "Ed Balls was in the year below me. I lent him my O-level history notes and he never gave them back."
He formed a school debating society, but was drawn to the mechanics of political debate rather than the ideology. "Not having a father, we didn't hear from him at the table," he says. It was only years later, when he had become a Lib Dem activist, that Mr Davey discovered a newspaper clipping in a photo album with the headline, "Only the Liberals understand the NHS", over a photo of his father speaking at a Liberal garden party. "My mother hadn't talked about it. That meant a huge amount to me to know that my father, who I had never really known, had been attracted to the Liberals. So maybe there was something in the DNA."
His first taste of party politics came when his brother Charles took him to a Young Conservatives disco. "I sat in the corner and felt very young and very out of place." Later he went to the Labour Club at Oxford University. "There was a young David Miliband and a young Steve Twigg, and I listened to some debates and I'm afraid I was put off." It was because of "the quite statist and socialist tendencies" of the future New Labour standard-bearers.
In his gap year he travelled, read books on environmentalism and worked in a pork pie factory for a fortnight, was a postman and worked at Boots.
He supported an unsuccessful tactical campaign to get Chris Huhne elected as the SDP-Liberal Alliance MP for the Oxford West and Abingdon seat in 1987. Last month he replaced Mr Huhne when the latter was forced to resign from the Cabinet after being charged with perverting the course of justice. Mr Huhne is a "valued colleague", he insists, and there will be little change in direction at his department. Promotion did not "come out of the blue". "The speculation had been going for some time."
But where Mr Huhne would readily take the fight to his Tory coalition partners – notably haranguing George Osborne across the cabinet table – Mr Davey is more diplomatic, refusing to be drawn on details of the Budget. He allows himself a slight dig, which will irritate some on the Tory back benches. "They wanted inheritance tax cuts for very, very wealthy people, and that's not happening. We wanted tax cuts for the low paid, and that is happening." He also "strongly supports" David Cameron's insistence to Tory MPs that there are "perfectly hard-headed reasons" for more onshore wind turbines.
Mr Davey's in-tray at the Department of Energy and Climate Change is full. He will have to resolve the chaos resulting from the decision to cut solar panel subsidies, tackle soaring energy bills and oversee the Green Deal – an ambitious plan to pay for homes to become more energy efficient with loans secured against future savings on bills.
And nuclear remains a sticky issue. In opposition, he criticised the "safety and environmental risk" of new reactors, as well as the cost. Now he says that a large number – although not all – of Lib Dems are actually pro-nuclear. The need to tackle climate change has required a new approach. After all, "nuclear is a low-carbon technology".
Ironically, the minister in charge of saving the planet was in fact once turned down for a job at Friends of the Earth before joining the Lib Dems, where he was an economics researcher, inspired by its then leader Paddy Ashdown and the party's environmentalism. There, he advocated giving the Bank of England independence, a policy ridiculed and then implemented within days of New Labour's 1997 election landslide.
Those were the days of opposition oblivion. Now, as the Lib Dems gather in Gateshead for their spring conference next weekend, they are struggling to survive as a party of government. Mr Davey insists morale is good. "I joined the party when we were on 4 per cent in the polls. At the time, we were an asterisk in Scotland, our vote was so low it barely registered."
He uses the word "resilient" a lot, both about himself and his party. Each setback in his life, he says, has made him stronger. His reputation in Westminster is that of a steady-as-she-goes safe pair of hands. Yet he has a determined streak which he traces back to being orphaned at 15. "There was a time before my O-levels when I remember thinking I used to study hard and work hard to please my mother, like most young children. And then I realised I'm doing this for me."
1965 Born Edward Jonathan Davey on Christmas Day, the youngest of three sons. Father, John, dies when Ed is five, and mother, Nina, when he is 15.
1974 Attends Nottingham High School, in the year above Ed Balls.
1985 Studies philosophy, politics and economics at Jesus College, Oxford.
1989 Starts working as an economics researcher for the Liberal Democrats.
1994 Saves a woman's life after she falls on the tracks at Clapham Junction. He later receives two bravery awards.
1997 Elected as Lib Dem MP for Kingston and Surbiton. Majority: 56.
2001 Becomes frontbench Treasury spokesman, serving as chief of staff to the leader and running campaigns.
2005 Marries Emily Gasson. They have a son, John Alban, 4.
2007 Runs Nick Clegg's leadership campaign.
2009 Sparks controversy when he tells Lib Dem conference Britain must hold talks with the Taliban.
2010 Joins coalition government as business minister, winning plaudits for privatising Royal Mail and championing consumer rights.
2012 Promoted to the Cabinet as Secretary of State for Energy and Climate Change, replacing Chris Huhne.