This week Dame Edna Everage returns to British screens for the first time in 15 years with The Dame Edna Treatment. “Making room” in her “hectic schedule” for “us”, this time around, Everage is running her own “exclusive health spa”, into which various celebrities will be dropping. Confirmed so far are Martin Sheen, Alec Baldwin and Susan Sarandon, while Dame Edna will be duetting with singers as diverse and, frankly, bizarre as Englebert Humperdinck and Fergie from the Black Eyed Peas. Sir Les Patterson will be popping by — God knows how they managed to book him — and, for added mirth, Everage 2007 also brings with her a daughter, Valmai, who is a kleptomaniac.

Although not a great deal of extra detail has been forthcoming, it's pretty safe to assume that, given the “health spa” setting, there will be a great many jokes about colonic irrigation. Still, like anyone with a famous catchphrase, Everage has long been aware of the comic advantages in a certain amount of predictability. The best colon jokes are — perhaps [[ like the best colons — well-established and regularly used. When all’s said and done, there is nothing like a Dame.

Except, of course, there now is. When Dame Edna Everage was in her imperial phase in the 1980s — stalking the schedules like a sequined T Rex — she was way ahead of the curve. Having come up with an irreverent, celebrity-obsessed, monomaniacal, drag-queen chat-show host, Barry Humphries probably felt he didn’t have a great deal of competition. As far as I recall, Mavis Nicholson, motherly host of daytime chat-show Mavis, never told Joan Rivers: “You should always be ready to laugh at yourself — you might be missing out on the joke of the century.”

Humphries’s schtick was, at the time, unique. And back in the days of four-channel television and grey duvets, Everage was about as big a deal as you got on TV. Despite her chat-show being on ITV at 10.30pm on Saturday night, all the kids in my playground could do impressions. I recall Richard Drinkwater, the one-eyed Jehovah’s Witness, turning up to assembly late. He came through the double-doors and registered a silent, aghast room. To his credit, and subsequent legend, he took this moment of silence to fling his arms wide and say “Hello, possums!”

In 2007, however, the market Everage returns to has seen a great deal of action. Caroline Aherne (Mrs Merton), Steve Coogan (Alan Partridge), and Rob Brydon (Keith Barret) have used the concept of fictional characters hosting chat-shows. For monomaniacal hosts who won’t let the guest get a word in edgeways, we’ve had Jonathan Ross and Clive Anderson. Salacious innuendo has been supplied by Graham Norton, Lily Savage, Julian Clary and Ross again. And as far as the outrageous outfits go, whatever Everage has worn as a joke, Jordan has worn for real, to her own wedding, with pride. As Everage herself would no doubt say, her furrow has been repeatedly ploughed. Who knows if it has any more to give?

But, of course, the schtick Everage is mining is as old as the hills. Dame Edna is Widow Twankey — often with exactly the same wardrobe. The set-up doesn’t vary a jot from the average Christmas production of Cinderella — with the hapless celebrity, cast as the princess or prince, having to gamely “take the joke”, as Humphries works in a knowing reference about their career. No, while Everage’s territory has been encroached upon, it should be solid enough to weather rival incursions.

In Everage’s case, the question is simple: can Australia’s twelfth biggest export — after Nicole Kidman, Russell Crowe, Kylie, Neighbours, Home and Away, the barbie, Foster’s, the UV-proof swimsuit, the Wiggles, sturdy nymphomaniac backpackers and a ballsy line in shiraz — actually still hack it?

Without any preview tapes being handed out — episodes are being filmed close to transmission — it’s hard to tell. So we must, instead, fall back on Everage’s last public appearance in the UK. At last year’s Sony Radio Awards, Everage was the surprise guest — called upon to present Sir Terry Wogan with his Lifetime Achievement award. Perhaps a little unsteady on her feet, Everage made her way down the staircase and into the room to thunderous applause; dressed, as ever, like Matthew Williamson’s cutting-room floor. Her speech on Wogan’s career had the whole room, including Wogan, helpless with laughter and, at the end, the standing ovation seemed like it was more for Everage than Wogan. Her comments were, simply, gigantic insults delivered in the familiar, winsome manner, and, to be fair, most of the speech was about Everage, rather than Wogan, who was standing, highly amused, next to her, rendered unexpectedly silent.

But do you know what? I can’t recall a single thing she said.

The Dame Edna Treatment, tonight, ITV1, 9.40pm

AN AUDIENCE WITH DAME EDNA

What can we expect from your new show? You can expect to see an international gigastar at the height of her powers and if you don’t believe me, ask my gynaecologist!

I read that you are going to have “real stars” on your show, not “celebrities”. What do you mean? Celebrities are the new nonentities! Sorry, call me old fashioned, but they are. They’re on everyone else’s talk show and on those stupid reality shows which are already a bit old hat. Everyone on my show is red-carpet material and a personal friend, and it’s not a show anyway, it’s an intensive course of TLE (Tender Loving Edna).

We Brits had started to give up hope of hearing from you again. What have you been up to? I was the first high-profile person since Columbus to discover America and at this point in their history, that sad little country needed me more, much more, than my little English cousins. They showered awards on me on Broadway; the White House insisted that I tour the land spreading my message of caring and sharing. But in the end my British heritage called me back here. The Queen also had a tearful word with me, needy little mite that she is.

I hear the Bee Gees are involved. Are they fans? I’ve known those boys since they were bubbas. I shared their hopes and fears and their laughter and tears, not expecting anything in return. When they heard I was doing this exclusive course of TV treatments for ITV they said: “Can we write you a theme tune?” Who could say no to that, possums!

You have tremendous energy. What’s your secret to remaining so eternally youthful? Everyone morning I look in the mirror and I say, “Edna, you’re gorgeous” three times. Substitute your name for mine, possums, and you will sail through the day as energetically I do.

Can you give us some idea of what your spa is like and what treaments you suggest for some of the world’s megastars? My treatments are very private and if, for example, I was giving a major star colonic irrigation I would hate it to leak out. Enough to say I’m running the world’s most state-of-the-art facility. Tune in tonight and you will get a personal guided tour.

What’s your greatest achievement? The creation of the Prostate Olympics. I also have the world’s first urological theme park in development — Prostate World.

Who would you like to portray you in a film of your life? A much younger and more attractive Helen Mirren. The Queen wanted me and not Helen Mirren to play her in her film, but I had to turn it down because I looked too young.

If you could change anything about your life what would it be? I would erase the day I signed my life away to my manager Barry Humphries. He’s been embezzling from me ever since.

What keeps you awake at night? That my popularity will go out of control.

What do you consider your most unappealing habit? Chronic modesty.

Interview by James Jackson

WHAT SHE MEANS TO US

Australian comedienne Caroline Reid, aka Pam Ann “Barry Humphries was at a wedding I was at, and he was standing next to me. Someone kept doing that thing where they tap you on the shoulder and you turn around and there’s no one there, and I thought ‘There’s no way he’d do that.’ But then I looked at him and he had a cheeky glint in his eye, and I asked if it was him. He replied, ‘Lovely dress.’

“I grew up a few suburbs away from Moonee Ponds, where Dame Edna is from, and I’ve always been inspired by Barry Humphries — to me, he is the Madonna of comedy. He really paved the way for that kind of character comedy.” Pam Ann is on tour with her new show, One World Alliance (www.pamann.com)

Richard Ingrams, former Private Eye editor (below) “I met Barry in the 1960s [Humphries drew cartoons for Private Eye], and Dame Edna in those days was quite different. When she first appeared on the stage she was a very modest little Australian housewife clutching her handbag, and rather drab. I can’t remember at what stage she developed into the Edna we know, but one moment I remember very well was when I attended one of the An Evening With . . . programmes. At the end, when Edna was hurling her gladis into the audience, one of them hit a man in a wheelchair, and his chair shot off the steps he was on and slipped right down to the bottom and he was left spreadeagled! There was a moment of terrific shock, and then the bloke just got up and walked away — it was all a stunt! It was a brilliant moment but they didn’t show it when the programme went out — a pity.”

Michael Walters, Dame Edna impersonator, Orlando “Initially, my recreating Edna was just a fun way to bring a new twist to a rather bland drag character in a rather poorly written script — I thought Edna’s offbeat delivery would make even the most unfunny lines land huge laughs, and it worked.

“Barry was always well ahead of his time. The genius of his creation lies within the reality of the character. Edna is not Barry Humphries — she’s her own person. I’ve met Barry on several occasions, but I have yet to meet the lady herself. I’d much rather meet Barry, though. Edna, I fear, might not approve of a man impersonating her, dressing in replicas of her son Kenny’s one-of-a-kind frocks.”

Brendon Burns, Australian comedian and Ednaphobe “Dame Edna was one of those people who is famous in Australia for being famous overseas — like Rolf Harris. You know why Dame Edna is popular in Britain? Because you’re still stuck in panto era: bloke in a dress, high-pitched voice, purple hair. I couldn’t stand it when I was growing up, because the voice reminded me of my mum nagging me. I spoke to someone who used to write for her and she said it was so frustrating because it was really difficult to get her to talk about anything other than sagging body parts. Every gag is like ‘Oh! My boobs now look like wind socks on a drizzly day!’ It’s not for me.”

Brendon Burns is at the Soho Theatre (www.sohotheatre.com) from March 19. Interviews by Louise Cohen

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