By Brian Wheeler
BBC News political reporter
Zac Goldsmith was once quoted as saying the only way he would vote Conservative was if you "drugged" him first.
Goldsmith: "I'm cynical about politics"
"I can't remember saying that," he protests when we meet at the Chelsea offices of The Ecologist, the magazine he edits, "but it is not a million miles from how I felt".
Mr Goldsmith was one of David Cameron's more surprising signings when he took over as Conservative leader in December.
His father, the late billionaire financier Sir James Goldsmith, did, after all, help to eject the Tories from power in 1997 with his eurosceptic Referendum Party.
But as deputy head of a policy review group, 30-year-old Zac will play a key role in formulating Tory policy for the next election.
"If you had asked me six years ago would I want to be part of the Conservative Party I would have said no," Goldsmith says.
"I am cynical about politicians. My experience of politicians has been thoroughly negative. I have found that politicians are people that can not be taken at face value. There are very few politicians I have been impressed with."
Mr Cameron is one of them, it seems.
Goldsmith says he had not met the new Tory leader until he won the leadership election. His main point of contact with the party had been Oliver Letwin.
"I don't know David Cameron very well. I like him. I think you can judge a book by its cover - whoever said you can't is wrong - that's the whole point of nature giving us intuition, instinct and so on.
"I think the cover is pretty good. I think the people he has got around him, who are helping him to craft this new identity, are good people so I am genuinely enthusiastic about it."
Articulate and engaging, Goldsmith speaks with almost manic energy, pausing only to re-light the roll-up cigarettes he chain smokes throughout the interview.
As editor of The Ecologist, which was founded 30 years ago by his uncle Teddy, he is used to being in the spotlight.
He has, among other things, fought high profile campaigns against biotech giant Monsanto, campaigned against nuclear power and what he sees as the overweening power of the big supermarkets.
The Tories have made the most of their new signing
The walls of the magazine's slightly shambolic offices are covered in anti-globalisation posters.
His considerable personal fortune enables him to bankroll causes close to his heart, he explains, and, if necessary, take on the multinationals in the libel court, something, you sense, he relishes.
"I can't be bought. I don't need to be bought. I'm not a careerist. I don't need to have a career in politics. I'm in a very, very luxurious position, but I am in a position of strength. I think I have been selected by Cameron, within the context of that understanding."
He chose to back the Tories because Labour has become "the party of big business", he argues.
"You can judge Mr Blair's position on almost any issue on the basis of what would the big lobby groups want him to do," he argues.
But he acknowledges the Tories must also take their share of the blame.
"I would never want to be in a position where I am defending the Conservative Party's record. If they did a good job in government there would be no need for the review process that David Cameron is launching."
The policy review, to be headed by ex-minister John Gummer, has been given a "blank cheque" to come up with policy ideas - including, if necessary, tax increases in areas such as aviation fuel and tighter regulation, he says.
Sir James: "Like a military commander"
And, curiously given his late father's views, he cites the European Union as an example of what politicians can achieve when they put their minds to it.
"There are all kinds of problems with the European Union but nevertheless these things are possible. How can putting a tax on aviation fuel and going through that negotiation process be any harder? It's clearly not harder than establishing a European Union."
The thought that Mr Cameron would - having commissioned the policy review in the full glare of publicity - reject its findings or "kick them into the long grass" is, in his view, "just not conceivable".
"Obviously if we came up with mad proposals they would be rejected but we don't intend to come up with mad proposals," he adds.
Goldsmith, who is on the Conservatives' candidate list for the next election, says he has been surprised by the level of media interest in his new job ("the party has made quite a big deal of this review process").
But he insists he would not be doing it if he did not think it could eventually make a "real difference to the way Britain is governed".
"I try not to take punts unless they have a reasonable chance of success," he says, reaching for a familiar gambling metaphor.
Zac Goldsmith's sister Jemimah
The son of Sir James and his third wife, Lady Annabel, Goldsmith traces his interest in environmental issues back to a childhood fascination with David Attenborough's nature documentaries ("I think we owe him a huge debt").
In his early teens, he says, "there came a point where I began to realise the world was under siege more than at any time its history and that was pretty depressing. I suppose that ignited my anger and commitment".
Expelled from Eton after drugs were found in his room, he did environmental work in the Himalayas, before taking over The Ecologist seven years ago.
Not having to work for a living, gave him the "freedom to breathe" and think seriously about the environment, he says.
As the brother of Jemima Khan, currently linked in gossip columns to film star Hugh Grant, he is no stranger to seeing his name in the papers.
But he insists his media profile helps him to mount more effective campaigns.
"If you read an article about yourself, it's always cringe making. But the reality is I couldn't do what I'm doing now without that."
As for stories of his playboy lifestyle and his love of gambling, he says, with a smile, he is "not a monk", but insists tabloid tales about him losing a small fortune on a single hand of poker are pure fiction.
In any case, he argues, he has three children and a farm in Devon - as well as the magazine - to keep him occupied.
"I don't have a particularly extravagant life. I do what I want to do. I enjoy doing what I do. If there was a time when The Ecologist appeared not to be making a difference at all, not doing something useful, I wouldn't do The Ecologist, but I think it is useful."
His father, Sir James, shared his passion for the environment, he says, and secretly backed green causes, including anti GM Food campaigns and the McLibel Two ("he liked what they were doing. He thought they were plucky").
"He was a very odd character," Goldsmith says, recalling the father he hardly knew as a boy.
"I remember knocking on doors in Putney, asking people to vote for him. Some people loved him, other people thought he was the most terrifying creature they had ever heard of, and they thought he wanted to became a sort of dictator of the country.
"And you can understand that. He was a very exotic character. His family life was exotic. Everything he did was different. I have never met anyone like him and I shouldn't think I ever will meet anyone like him.
"So I am not surprised he had a rough time. He didn't mind that. He was sort of like a military commander. He was used to hostility."
When he was nine, the young Goldsmith started a "budgerigar sanctuary" in his Richmond back garden, collecting unwanted birds from the neighbourhood to be released into the relative freedom of an old chicken coop.
"I hated the idea of birds being kept in cages," he says by way of explanation.
The birds that didn't take well to their new found freedom, he trained to fly by perching them on his finger and forcing them to flap their wings, "to build up the muscle".
"It was a very weird thing to have done," he says with a smile, "but anyway it worked".
He will be hoping for a similar verdict on his venture into party politics.