Joanna Lumley: The avenger

The idea began on Twitter. Then the blogs took it up. Finally the notion ended up on the front page of the one newspaper in a headline three inches high. Joanna Lumley for Prime Minister, was the message.

The weight of the political blow dealt to Gordon Brown by Britain's most effortlessly elegant actress this week left political commentators grasping for similes. The victory of Joanna Lumley's campaign to get the Government to reconsider its refusal to allow the British Army's former Gurkha soldiers the right to settle in the United Kingdom was, said one of our most seasoned political pundits, equivalent to six by-election defeats in terms of the damage that it does to the authority of the PM.

She will not demur from continuing the fight. The Gurkhas' plight has been close to her heart for longer than most politicians can imagine. "I can't remember a time when I did not support their cause – I have always felt like a child of the regiment," she said recently.

It is not hard to understand why. She was born in Kashmir where her father was a major in the 6th Gurkha Rifles. Among the elderly veterans whom she accompanied to 10 Downing Street this week was the 86-year-old Tul Bahadur Pun, who in 1944 won the Victoria Cross in an action against Japanese machine-gunners in Burma during the Second World War. Among the many British lives he saved that day was that of Ms Lumley's father. "Ever since I was a child," Ms Lumley said, "this man has been my hero."

Joanna Lumley was born two years after that day of Rifleman Pun's extreme gallantry. A year later she and her mother left India to join her father's regiment in the Far East, where she spent most of her early childhood. She was a child of the Orient.

When Joanna, aged nine, was sent "home" to school, it was England which seemed the alien place. "I remember being homesick, having been brought up in the Far East, with its heat and storms and vivid flowers and sounds and smells," she has recalled. "England seemed strange and cold and pale and misty."

At boarding school in Kent she kept mice in her underclothes drawer. "It made me smell most attractive, as you can imagine." At 16 she auditioned for the Royal Academy of Dramatic Art, but was turned down. Instead she went to the Lucie Clayton finishing school where, among other things, she was taught that ladies only cross their legs at the ankle.

The tall slim leggy blonde with brilliant blue-green eyes got a job as a model. It was the Swinging Sixties and soon she was working with the leading designer Jean Muir and being photographed by society snappers like Patrick Lichfield. Next she became a household face as the girl dangling dangerously from a hot-air balloon in a television ad for Nimble, a slimmers' bread. In 1969 she landed a part as a Bond Girl in On Her Majesty's Secret Service. The script described her only as "the English Girl", but that was apt enough for an actress who was to play variations on the theme of English Rose for the next 40 years. She is a beauty, someone once said, "who looks as if she's made entirely of hand-cream, poetry and champagne".

But her career was not to be so effortless as her elegance. In 1970 she married the comedy writer Jeremy Lloyd. A year later the marriage was over, and one Saturday matinee she simply failed to turn up to the theatre in which she was starring in It's Awfully Bad For Your Eyes, Darling. "I did a Stephen Fry and I never went back," she said later.

After her nervous breakdown she returned to acting. In 1973 she did 103 episodes of Coronation Street and turned down an offer of marriage from Ken Barlow. Of those years she has said: "I had no money, I was a single parent. We were poor but we weren't unpleasantly poor; we weren't starving. It was a hard slog."

But in 1976 came the first role that would make her a household name. In a re-make of The Avengers (The New Avengers) she played a karate-kicking secret agent called Purdey. It propelled her to instant fame, not least for the sleek page-boy bob created for the character by Nicky Clarke. Women across the land demanded their hairdressers emulate it.

It was also in the 1970s that Joanna Lumley, while eating a steak one day, had a vision that it could have been cut from her own arm. She became a committed vegetarian. She has been a crusader for animal rights ever since, and for much else.

Despite one newspaper yesterday praising her for not being not one of those celebrities who "busy themselves adopting African orphans or grandstanding at UN conferences", she has quietly been an activist for decades. She has long espoused the cause of a free Tibet and of human rights in Burma. She supports the mental health charities Mind and SANE. She has been to Africa several times for Comic Relief and to Bangladesh for Sight Savers International. She backs Book Aid International, which distributes books for free in developing countries. Her advocacy of the Gurkhas' cause, dear though it may be to her, is far from an isolated concern.

Her concern for people in difficulty perhaps reflects that her own career has not been a smooth transition from one success to the next. After The New Avengers came three years on Sapphire and Steel, ITV's answer to Dr Who, of which it is kindest to say that it had "a cult following". She returned to the theatre and had cameo appearances in The Pink Panther and other films. But her private life was happier. In 1986 she married her present husband, the conductor Stephen Barlow.

She got lots of work doing advertising voice-overs and had hits with personality television shows like Girl Friday in which she was purportedly left to fend for herself on a desert island for 10 days (but ended up cadging cigarettes from the camera crew). And she was made a Fellow of the Royal Geographical Society after an arduous trek through the Himalayas to Bhutan for a programme retracing a journey her grandparents had made.

But she did some of her finest work in this period too. In Up in Town, a series of 10-minute television monologues, she shifted the breathy sexiness of her voice into the harder-edged poshness of an upper-class divorcee, applying her make-up as she looked into the camera, and talked about her life with a profound unconscious poignancy.

What brought her to a new generation was her character in Absolutely Fabulous, which ran off-and-on from 1992 to 2005. Her creation of the beehive-haired, chain-smoking, champagne-quaffing, cocaine-sniffing fashion monster Patsy Stone revealed to the nation a sense of comic timing as precise as her accent – which she now overlaid with Estuary vowels to create a character who became an icon of the thoughtless greed and hedonism of the Nineties. It was one of those great comic creations that the British public pretended to hate but really loved. "Patsy is the other person I could have been, if I hadn't turned out to be me," Lumley later said.

Don't you believe it. The lovely Joanna Lumley could not be more different from the addled Patsy Stone if she tried. The two of them may smoke but there the similarity ends.

Lumley is, at heart, an old-fashioned gel with impeccable manners. "I think we have got some of the prettiest and loveliest girls in the world but sometimes the behaviour gets a bit bad and the girls let themselves down," she says, sounding like her old headmistress. She says things like, "I can't see any difference in having your hair dyed, your teeth fixed, your nose done, or your face smoothed out or lifted". But she has never herself resorted to plastic surgery. And she is so jealous of her privacy that she has said that if she could she would ban "cruel and hateful" celebrity magazines.

But it is all said with a characteristic and very English self-mockery. "I feel myself as shallow as a puddle," she concludes, unconvincingly. As a result the nation either lusts after her, discreetly of course, or is charmed by her. Not the kind of thing we expect from a prime minister.

A life in brief

BORN: 1 May 1946, in Kashmir, India.

FAMILY: The daughter of James Rutherford Lumley, a major in the Gurkha Rifles, and Thya Rose Weir. She has a son, James, and two granddaughters. She lives in London with her third husband, the conductor Stephen Barlow.

EARLY LIFE: Her family moved back to Britain in 1949. She attended army schools in Hong Kong and Malaya. Her television debut was in 1969's Some Girls Do.

CAREER: It was as Purdey in The New Avengers, Sapphire in Sapphire and Steel and Patsy in Absolutely Fabulous that she earned her place in the pantheon. She was made an OBE in 1995 and is a spokesperson for the Free Tibet movement and the Gurkha Justice Campaign.

SHE SAYS: "If you love something with a passion, it must come from within you. You are what you do, and you get what you want. That's why I'll always put my hand up."

THEY SAY: "She has tirelessly and loyally offered support to our cause." – Karma Hardy, director of the Tibet Foundation