Profile: Emma Thompson

LIKE a giddy aunty who delights in telling amusing stories before blurting out something she oughtn't, Emma Thompson is at it again. After a visit to her old school, the 51-year-old Cambridge-educated actress, famed for her plummy tones, spoke out against the use of sloppy English and slang words such as "likes" and "innit", adding that the failure of many children to speak properly drove her "insane".

It is just the latest in a long line of headline-grabbing remarks from the outspoken actress who in a recent appearance on The Late Late Show with Scottish comedian Craig Ferguson said that homosexuals were flogged and Scots were shot on sight on the Isle of Wight (she later apologised - it turned out she meant to say the Isle of Man). Prior to this Thompson commented that Exeter was "very white" and was a place where BNP leader Nick Griffin would feel at home. She also upset Audrey Hepburn fans by asserting that the screen legend couldn't act or sing.

In spite - or perhaps because - of all this, Britain loves Emma Thompson. Sisterly, slightly naughty, and an all-round good egg, Thompson is one of the few people dubbed a national treasure who might actually deserve the title. Widely considered by those who have worked with her to be one of the nicest, least starry people in showbusiness, her pals include Meryl Streep, Dustin Hoffman and Maggie Gyllenhaal. Describing Thompson as her biggest inspiration, actress Helen Mirren said: "She's a remarkable woman and is an amazing advert for women in my profession. She's beautiful, a brilliant actress and very clever. She can write and she speaks out for what she believes in."

• Emma Thompson: Facts of Life

Middle age is usually a treacherous time for actresses, but Thompson is busier than ever. She is reportedly in negotiations to join the cast of Men In Black 3, playing the lead role of MIB Agent Oh alongside Will Smith and Tommy Lee Jones. It is an interesting career move for Thompson, a gifted character actress and leading lady, who moves effortlessly between period dramas, art house films and mainstream Hollywood offerings. In recent years she has devoted more time to writing, including a new version of the musical My Fair Lady and the screenplays for the wildly popular Nanny McPhee children's films, in which she starred as the titular character, complete with warts, wonky teeth and a fat nose.

Professionally, Thompson is, in the words of Kirsty Young on Desert Island Discs, "a study in over-achievement". The actress, who speaks fluent French and Spanish, is the only person ever to win an Academy Award for acting (for 1992's Howards End) and writing (for the screenplay for Ang Lee's Sense And Sensibility in 1995).She champions human rights and environmental causes and campaigns against human trafficking (the subject of Fair Trade, the play she produced at this year's Edinburgh Fringe).

Though she loves her work, the star is happiest hanging out at home in London with her second husband, actor Greg Wise, and daughter, Gaia, 10. "Sometimes I get to put on posh frocks and be Madam Glamour… but my real life is very different. It's very, very home-based - an intense domestic life, that's the core of everything," says Thompson, who still lives in the same street in West Hampstead where she grew up. Her mum, the Scottish actress Phyllida Law, lives just across the road and the two are forever in and out of each other's houses. Thompson's actress sister Sophie lived on the same road too until a recent move took her to a new home two miles away. Em can regularly be seen popping out to the shops without make-up or bodyguards and freely mocks herself whenever the opportunity rises.

Born into a family of actors on 15 April, 1959, Thompson had a happy childhood, filled with laughter and creativity. Her father was Eric Thompson, who scripted and narrated the children's television show The Magic Roundabout. When he died of heart failure in 1982, aged 53, she became severely depressed - a condition which has dogged her on and off throughout adulthood. She recalls spending her days in a daze, unable to take a shower or get dressed, and then turning up for work at the theatre at night.

A bright, popular student, she went to Camden School for Girls (former pupils include Sarah Brown, Arabella Weir and Geri Halliwell) before going on to study English literature at Cambridge University. There she shaved her head, dabbled in feminism and rode around on a motorbike. Precociously talented, she had an agent two years before she graduated and was part of Footlights, along with Stephen Fry and former boyfriend Hugh Laurie. Fry said of their first meeting: "I remember having a distinct sense that here was a somebody." In 1981, she, Fry, Laurie and Tony Slattery, became the winners of the first ever Perrier Award at the Edinburgh Fringe.

After a universally panned TV sketch show in the early 1980s, Thompson's career took off. She met her first husband, Kenneth Branagh, on the set of Fortunes Of War in 1987. Ken and Em married two years later and became the ultimate luvvie couple. She made 12 films and won her two Oscars, and a pile of Baftas and Golden Globes, before she and Branagh divorced in 1995 amidst rumours of his infidelity. She is said to have drawn on the breakdown of her marriage to Branagh for her moving, understated turn as the wronged wife in Love, Actually.

Thompson and her second husband met during filming of Sense And Sensibility after Wise was told by a fortune-teller that he would meet his future wife on his next film.He assumed it must be co-star Kate Winslet and set about courting her only to fall in love with Thompson after they shared a private plane to Cannes. Wise is seven years Thompson's junior and she once gave him a framed copy of a tabloid newspaper story describing him as her toyboy. "Greg was thrilled. We were squealing with laughter. In fact, if I never wore make-up again, he'd be completely happy. He loves me whatever way I am." The family spends a lot of time in their second home just outside Dunoon, which Wise built.

After several unsuccessful IVF treatments, the couple unofficially adopted Tindy, a refugee from Rwanda, who they met at a Refugee Council party in London when he was 16. Thompson said, "He's such a lovely, enchanting boy, so I said, 'Come and have Christmas with us.' And he came for half the day. Slowly, he became a sort of permanent fixture."

Reflecting on her career, the modest actress, who received a star on the Hollywood Walk of Fame in August, said, "I do sort of think 'Wow, how did all this happen?'"