It was a busy week for Emma Thompson – a week of contrasts, too. First up, came the Golden Globe awards in Los Angeles – so we had glam Emma, the luvvie. By midweek, though, she was back this side of the Atlantic, the earnest campaigner prepared to do anything, including buying up a field in west London to stop the Government from going ahead with its plan for a third runway at Heathrow.
It was hard to escape her – every time you switched on the telly or passed a paper stand, there she was. By Friday she was trading insults with Geoff Hoon, the Transport Secretary. He stated that he didn't "see the logic of her position... The last time I looked the only way to get from LA to Britain is Heathrow". Thompson briskly retorted, "Get a grip, Geoff. This is not a campaign against flying... It sounds like the Transport Secretary has completely missed the point. Again."
So it seems opportune to ask her what she says to people who feel they've, quite simply, had enough of her. What does she say to those critics who've had it up to here with star-spangled, leftie campaigners who seem never to be out of the public eye, always banging on about something or other that they're utterly, totally passionate about?
The funny thing is that she's sympathetic to their view. The truth is, she says, she can see where they're coming from – she feels herself she's been a bit too all over the place these past few days. "It's all been a bit of a hoo-ha," she says simply.
But the point about last week, she explains, is that so much happened at the same time – and being the sort of person who just gets on with stuff, she just got on with it. "There were the Globes and all that showbiz nonsense, and then Heathrow and I think people probably are thoroughly fed up with me," she goes on. But she does make a hard-headed calculation. "I don't appear on the news lightly. It's something I think about very carefully. I think the last time was probably the Gulf War, but what I feel is that we all need to speak up and a woman who has got a louder voice needs to shout very loudly indeed." But now she's planning to melt away. "I'm going to shut up now. I've said enough for a while. I'm going to quietly disappear."
Oh, Emma, surely not? No, really, she says – even when Last Chance Harvey, the film she was nominated for as best actress in a musical or comedy at the Golden Globes (she was pipped at the post by Sally Hawkins for her appearance in Happy-Go-Lucky), opens here in June, she's going to keep a low profile. Rather ironically, the new film has Thompson as a civil servant who meets up with a down-on-his-luck Dustin Hoffman in a bar at Heathrow airport.
Over the past few days, her relationship with Heathrow has certainly been a lot more about politics than romance. She took the Government's decision to give the green light to a third runway as "a personal betrayal", and didn't think twice about weighing in. "I thought it was worth making the point for all the people in the country who have been quietly trying to do their little bit to reverse climate change. And then the Government shamelessly turns round and says, we are doing this! And they say they're doing it because there's a demand. There might be a demand for child prostitution, but that doesn't make it moral! The demand for more cars and planes is immoral. I thought we were being treated as though we were stupid."
Campaigning, she says, is in her blood; at Camden School for Girls, and then at Cambridge, she was going on CND rallies and shaking tins for Greenpeace. "It's not as though I've suddenly woken up and decided to campaign about the runway," she says.
Thompson has never shirked from the action when it comes to getting her passion projects on the right agendas. Last year, she went to the World Economic Forum in Davos. She couldn't stand it: the place was crawling with the men who run the world; most of the women there were spouses, and she won't be going again.
She much prefers Dunoon, the small, sleepy town on the west coast of Scotland that wouldn't know a world leader if one walked down its Argyll Street and ordered a coffee in the Tudor Tea Rooms. It's the place she calls "home, to us". The Thompsons have had a home there for decades, so by "us" she means not only her husband, the actor Greg Wise, and Gaia, their nine-year-old daughter, but also her mother and sister, fellow actors Phyllida Law and Sophie Thompson.
Even during last week's helter-skelter, Thompson was managing to fit in rehearsals for a new play in London about yet another issue close to her heart, human trafficking. Fair Trade, which she is producing, is inspired by the stories of two women, one from Africa and one from eastern Europe, tricked into coming to London, who end up being raped and forced to work as prostitutes and have sex with up to 40 men a day. The women on whom the play is based are still in the UK – one is HIV positive as a result of her experiences – and are seeking asylum.
Thompson is incensed by what she sees as the appalling prevailing attitude to women like these. "So many people think they just come here to make money, that they're just on the make, and it couldn't be more different. Their plight is so little understood, even by the Government – especially by the Government. Last year, every single person who sought asylum in the UK claiming they had been trafficked was refused it. It's as though the Home Office has just decided that this is a group of people they aren't going to have in the country."
Through her mentoring of the two young actresses who have written it and who appear in it, Anna Holbek and Shelley Davenport, Thompson has been pivotal to the development of the play. Holbek, when I call her during a break in rehearsals, explains how she was "a complete nothing – I was barely making the tea" on the set of Brideshead Revisited last year when she started chatting to film's star, Thompson. "She took me under her wing," says Holbek. "She could see I was a young actor – I was just out of the Italia Conti school – whom she could be helpful to. When I think back over what's happened since, it feels like a bit of a dream."
Holbek got involved with Thompson's art project The Journey, an installation in Trafalgar Square in London highlighting the experience of a trafficked woman, and when she and Davenport wrote a play about trafficking, Thompson lent it her support.
"The day she had us over at her house to read through the script was one of the most nerve-racking of my life," says Holbek. "But she was amazing. She said, 'This is excellent – let's do it.' She's the kind of person who decides she's going to do something, and then nothing stands in her way.
"Now we're about to open the play in London. Without Emma, we'd be lucky to be in some fringe place somewhere. But with her support, we're getting this work into the spotlight."
So while Thompson might be taking a break from the spotlight, she's unlikely to be out of sight for too long. She comes across as the sort of woman who, at 49, doesn't much care whether anyone thinks she's too uppity. It all sounds, though, like exhausting stuff; does she really believe any of it makes a difference? Doesn't she ever doubt whether, for all her influence and connections, she can change the world because the problems she's up against are so enormous? "You do think about that," she admits. "But, of course, finally you've got to come down on the positive side of the question. Because it's all the little efforts that do produce a shift in consciousness. And, what's more, to do nothing is unthinkable. It's simply not acceptable."
1959 Born in Paddington, London. Her mother is the actress Phyllida Law; her father, who died in 1982, was Eric Thompson, actor, director and creator of 'The Magic Roundabout'.
1977 After Camden School for Girls, studied English at Newnham College, Cambridge.
1986 Starred in the television series 'Tutti Frutti'; co-starred with Kenneth Branagh in BBC's 'Fortunes of War'.
1988 'Thompson' TV show flopped.
1989 Married Kenneth Branagh. The couple acted together in films including 'Peter's Friends', 'Dead Again', 'Henry V' and 'Much Ado About Nothing'; divorced in 1995.
1993 Won Oscar for best actress, for 'Howards End'.
1996 Received second Oscar, this time for best adapted screenplay for 'Sense and Sensibility'.
1999 Birth of her daughter, Gaia.
2003 Married partner Greg Wise and the couple adopted a 16-year-old Rwandan refugee.
2004 Named as one of 'Time' magazine's "European Heroes" in recognition of her work to highlight the plight of Aids sufferers in Africa.
2009 Bought land near Heathrow in protest against a third runway.
'Fair Trade' is at the Pleasance Theatre, London N7, 4-7 February www.pleasance.co.uk