You have only to walk into the office of BBC1's new controller, Lorraine Heggessey, to realise that something very radical is happening to Auntie. In the staid, almost sepulchral corridors on the sixth floor of Television Centre, a fizzing little thunderball has arrived to shatter the calm. Out have gone the white walls and black leather sofas, which - until now, at least - were a sign that BBC managers had made it to the top. In has come an explosion of colour: pinks and mauves all over the walls, tables, filing cabinets and bright blue sofas, and an array of children's toys: Teletubbies, dinosaurs, Eric the Gerbil - even a voo-doo doll to stand for whomever Heggessey is feeling fed up with.
And then there's Heggessey herself: petite, effervescent and wearing a bright mauve shirt that matches the colour-coordinated walls and even the carefully painted wastepaper bin. It all looks as though the team from Changing Rooms has been at work. No, she says, although she loves the programme, she has organised it all herself - and very cheaply, she adds quickly. But she means it to shock. This controller is different.
Heggessey admits that many people do a double-take when they walk in to see her: "They do, because it's not a conventional BBC office, and I hope I'm not a conventional BBC person, and I hope I never will be." She is so unconventional, in fact, that her first concern is to dispense publicly with "Auntie", the BBC's image for decades: "I'd like to shed it because I don't think it's an asset any more." So what is the BBC to be in future? Heggessey pauses. "A sister, maybe."
Which means exactly what? That BBC1 is set to become less educational and more fun. Heggessey laughs a lot and is certain that laughter is the key to restoring the BBC to its place in the nation's hearts. "Well, comedy is a fantastic thing to have in any schedule and anybody's life. Everyone feels better if they laugh, and one of the things I'd like people to start feeling is very warm about BBC1 . . . And one of the ways you do that is by uniting them through laughter."
Unity through laughter is not quite the Reithian world-view. But the BBC is under threat not just from ITV and media that are very quick to hammer it for dull programming, but also from the digital revolution, with the huge choice and competition it offers. The BBC has a seven-year deal on its licence fee, but beyond that, who knows?
Controllers are not paid to think about the longer-term business strategy; just creating a channel that is popular wins critical support and "works". By tradition, the Christmas scheduling battle is one of the most important moments in the year for any controller. Heggessey enthuses about "the most stupendous Christmas special" she has commissioned from Victoria Wood and a galaxy of stars; she is returning Lenny Henry to comedy after his forays into drama. The Christmas schedules, with "something for all the family", are just the start of her bid to put right the failings of the past on BBC1.
Heggessey is blunt about those failings: she agrees that the schedule was getting a bit predictable, and that the channel had "failed to deliver in popular drama and popular comedy". Too many "popular factuals" (such as Hotel and Driving School), she admits, were making the channel a bit "samey".
But isn't this move towards more comedy and entertainment further proof that the BBC is "dumbing down"? Absolutely not, according to Heggessey. Moving the Nine O'Clock News to ten was essential, she says, because "it was very difficult to launch new programmes off the back of the 'News at Nine' in a 9.30pm slot, when ITV had started some stonking dramas at nine o'clock". And she dismisses worries about Panorama's move from Monday evening to the graveyard slot on Sunday night: "It's five minutes later and one day earlier than it was before." She is confident that viewers are beginning to find the programme in its new slot.
In any case, Heggessey insists, although she can't imagine a BBC1 without strong factual and current affairs output, it will always have a "mixed ecology". A former science producer, she is passionate about the science programmes that have been brought into mainstream scheduling, such as Walking with Dinosaurs and The Human Body - examples both, she says, of "ground-breaking" television.
Heggessey's own career to date has been full of "ground- breaking" stuff. She brought us Animal Hospital, she has edited QED (the science-documentary series), as well as The Human Body, and spent two years as head of children's programmes. Petite she may be, but she is fearless, too. Famous for pursuing Roger Cook down the street, demanding he answer her questions, she has also left friends open-mouthed with stories of how she met hard-bitten criminals for her series The Underworld. Then there was the time she travelled around the Soviet Union with the reporter Richard Lindley, secretly filming dissidents, while they pretended to be a newly married couple on holiday. Her cover was nearly blown when one of the Soviet guides suggested the couple could not be newlyweds because they hadn't pushed their beds together. Heggessey and Lindley escaped - knowing that, had their deception been discovered, they could soon have been languishing in jail.
This fearlessness under fire translates into a less than sympathetic attitude towards shirkers at the BBC. Heggessey is right behind Greg Dyke, who announced to staff who didn't like the new BBC that they could push off. "The BBC doesn't owe you a job for life; nobody owes you a job for life any more," she says. "I've been a freelance and, basically, if you are good, people will ring you up and offer you work; if your show works, you'll get another show commissioned. If it doesn't, you won't - and people should accept that within the BBC."
That marks a stark contrast to the days when Auntie was happy to look after her workers for ever, finding innumerable "head of paperclips" jobs for those too drunk, disillusioned or just past their sell-by date to remain at the forefront of things. Heggessey signals a new, very different style of employer: "If you are ill, or if you have personal problems, the BBC is one of the most sympathetic employers ever . . . but it doesn't owe you anything beyond that. It can't just say, 'OK, you did great service for 21 years, so we'll employ you for another ten'."
Heggessey seems to have been cast from the same mould as the BBC's director general, Greg Dyke: small, dynamic, unconventional. She claims to have got on well with his predecessor, John Birt, but is more of a Dyke person: "I suppose I'm more naturally in tune with Greg's way of doing things, but that's because I'm a very instinctive person."
In her direct way, Heggessey hasn't shrunk from telling either Birt or Dyke what she thinks. She is scornful of those serried ranks of managers who seem to spend their lives at the BBC toadying up to those in charge: "One of the difficulties for senior managers in the BBC is that a lot of them seemed to be completely uncritical of everything that John did, and they can't now seem to be completely uncritical of everything that Greg does." It is said with a mischievous grin: this is someone who enjoys seeing the white, male, middle-class, Oxbridge-dominated top tier of the BBC shaken up a little.
She would still like to see a change in atmosphere at the top: "There's a lot of male behaviour that happens at board level that is very inimical to women . . . Well, they're all alpha males, aren't they? That's why they got there, and those are the qualities demanded. But I think women are much more natural team players, and they're not as egocentric."
She is thankful that the days of having to "drink the men under the table" are gone for working women, and is not ashamed to announce that she is taking time off for the school play or her daughter's birthday. Heggessey has two girls, aged 11 and eight, who are looked after mainly by her husband, Ron de Jong, a musician who works from home. Her personal life is "extremely important" to her: it also directs her thinking on the nine o'clock watershed, which she believes should stay: "I think you should be able to sit your children down safely in front of anything before nine o'clock, and you should pay a bit more attention after nine."
Controllers of BBC1 do not, these days, have a very long shelf-life. Heggessey's predecessor, Peter Salmon, was sacked after just three years. Heggessey has no illusions about the difficulties she faces, but appears undaunted: "It's really uncool to say that you love your job. But I do." Yet you feel that if it doesn't work out, she will go off and do something else quite happily: "If they don't offer me a job I'd like to do, I'll go and do a job I'd like to do somewhere else. Because life's too short; your working life does take a lot of your energy, and it does take a lot of your time, so you have to enjoy it."
She admits to feeling physically drained some days from the effort of trying to put her message across. "I can't make all the programmes, I can't possibly change all the programmes. What I've got to try and do is kind of infuse and enthuse the spirit of what I want to try and achieve into as many people as possible."
She is certainly doing that. Her assistant remarks, as she shows me out, that if the BBC could capture Heggessey's enthusiasm and bottle it, the corporation would be "very rich". The truth is, no one at the BBC expects to grow very rich on the licence-payer. What the Beeb wants is to be liked a little more by the many millions of listeners and viewers on whose support the organisation depends.
Either the BBC feels like a member of the family - someone you can share a joke with, grieve with, get the latest from - or it is heading for extinction. Which member, though? Once, under John Reith, it was a grim paterfamilias. Then it loosened up a little and became Auntie - the old duck who knew what was good for you but liked a naughty giggle, too.
And now? Everyone's sassy Big Sister would be quite a trick to pull off. But if anyone can do it, Lorraine Heggessey's the girl.