The author is in black, from stack-heeled boots to an expensive-looking cardigan. After hibernating all day in the study, writing, she has slapped on some bold red lipstick - for my benefit, she says. Even here, flanked by piles of recently washed children's clothes, with the scent of a roast beginning to permeate the air, there is something vampish about Ms Lette. Her movements are dramatic, the hands supporting every argument; but even when she's listening, and shifting in the chair or fiddling with an earring, the eye contact is full on. The eyes are large, like those of Kaa, the seductive snake in the Jungle Book video on her shelf, and they have the same ability to mesmerise...
Sorry, where was I? Better say something rude. That's not difficult, given the sheaf of cuttings in my hand. Each article is a savaging of Mad Cows, the dreadful new film of her novel. "A truly abysmal British comedy," said one critic of the movie, which stars Anna Friel, Joanna Lumley and Greg Wise. Another thought the attempt to put a Nineties spin on old-fashioned British farce fell hopelessly flat. "Never trust a film that advertises itself as mad," said the Independent. "Chances are it's just a bore in a wacky costume."
All this came after a mixed critical response to her last book, Altar Ego, which she thought was her best ever. Some agreed, impressed by the pun-rich prose, the way the dialogue crackled with one-liners. Others thought this fifth novel was a descent into comfort-writing, a joke wearing thin. Their subtext was that the brash, bolshy, deceptively bright and very Australian motormouth, who was so entertaining when she first came over 11 years ago, was in danger of outstaying her welcome - especially now that she is ensconced at the heart of the New Labour establishment, alongside her husband and fellow Antipodean, the human-rights lawyer Geoffrey Robertson QC.
Even for someone who makes a show of being thick-skinned, it must be hard not to be shaken by the visceral enthusiasm of some of the criticism. In the Daily Mail, for example, Christopher Tookey described the film as "a hideous memento of Cool Britannia... In years to come, this witless attempt at social comedy will be studied by hapless social historians as the definitive, sad relic of the period when the Blair revolution imploded and became New Laboured." It's only a comedy for heaven's sake, even if the credits do thank Chris Smith, the Culture Secretary. "We obviously Tippexed Tookey's name off our Christmas card list or something," Lette sighs. "But what can you say? You hand over your book and it's no longer yours. I got a nice little black dress out of it."
The producers of Mad Cows were unknowns, so there has been far more attention paid to the original book and its famous author than is usual. How much did Lette have to do with the preparation of the turkey that bore her name? "None. I offered to sleep with the cast. Well, Greg Wise. How edible is that man? But nobody was very interested." She did make one brief visit to the set. "I thought I could swan around with everyone saying, 'Oh, comedy goddess,' and licking my insteps, but it wasn't quite like that. They treat you like something they've trodden in. On the job desirability scale, in the film industry, it's amoeba, enema, tampon, writer. You sell the rights and have to let it go, but it does feel like your book has suddenly turned into a teenager - it's taking drugs, hanging out with people it shouldn't be with, and it won't come home and wash its undies. You have no control over it."
What did she think of the film? "I thought it wasn't the book. I thought it was an interesting interpretation." You mean it stinks? "No. It's got a couple of good jokes in it - when they stick to the book. Ha!"
Perhaps her vitriol is tempered by the part of her that loves hanging out with stars. Friends say she'll glam up at the sound of an envelope being opened, and the publicity department at Picador can have no complaints. "Anna Friel came round here to practise her vowel-flattening. The opposite of elocution classes. She was lovely. We had Joanna Lumley, comedy diva. Fabulous. And Greg Wise, the reason women don't need Viagra. They were so nice that I was not going to stab them in the front by not going to the premiere. Besides which we had a great party afterwards with nude male pole dancers." If the same people asked to film another of her books would she let them? "No. Is that enough on the movie now?"
We agree to move on, but then a good line occurs to her. Whenever that happens, Lette's eyes light up, those hands move involuntarily and she can't resist. "You know what was wrong? There wasn't enough bodily fluid in it. Where was the breast-squirting, and the mountains of haemorrhoids that Edmund Hillary couldn't scale?" Mad Cows, the book, bulges with gynaecological detail that makes men squirm and women guffaw. "The reason women related to that book is that no one tells you the truth about what it's really like to have a baby."
Without prompting, she slips into the old promotional routine, firing out clever lines. I find myself trying to guess which bon mots are spontaneous and which come polished by repetition and craft. Here's one for starters: "There are only three things you need to know about childbirth: one is to have the epidural; two is to not have the enema because crapping on the obstetrician is the ultimate revenge; and three is to get the doctor doing the episiotomy to keep on sewing. You don't want anything going in or coming out of there ever again."
In England, she says [and here comes another], new mothers don't like to complain: "It's that stiff upper labia. I used to think it was just me, but now I know that any mother who says she copes all the time is lying through her teeth or taking heaps of drugs."
Foetal Attraction is about a young Australian who comes to Britain and has a baby. It was written just after Lette gave birth (by Caesarean) to her first child, Julius (geddit?), who is now eight. "I was seriously deranged. It was either write that book or go into therapy. I was really, really depressed, so shattered with exhaustion." Did it help? "Oh yeah. It's so cathartic, much cheaper than therapy. And what also helps is when people write and say, 'I felt like that too.'" The sequel, Mad Cows, was provoked by the Conservative government's Back to Basics campaign, around the time her daughter, Georgie, was born five years ago. "They were demonising single mothers. I thought, 'God, if I'm finding it hard to cope and I've got all this support - a husband, I can throw money at things when it gets really tough - how do they cope? Then we found out all those Tories were going for gold, that they all had love children and mistresses and were going off to brothels, having eel insertion..."
Sorry? "Eel insertion. There's a magazine I saw in Soho the other day. Ages ago, actually. It was called Eels For Pleasure. Isn't that gross? I mean, you poor old Poms. It's too hot for all that debauchery in Sydney."
Too hot for eels maybe, but not for debauchery - as anyone who read her debut novel, Puberty Blues, would know. The promiscuous foam-filled life of a surfie babe made her a teenage sensation in her native Australia. "The girls were just sperm spittoons, human handbags. I wrote it for my girlfriends, so they would realise these barbaric guys were not the only men in the world."
Bunking off school to bonk on the beach was her act of rebellion against a happy upbringing, as the daughter of a famous Aussie Rules footballer called Merv. "Australia had a rough childhood but I didn't," says Lette. "There was nothing more dangerous for 100 miles in either direction than..." A bad prawn, I say, recognising the quote. "Well, I have to give you some lines. Isn't it hard? What do you do in interviews? Do you sit there like a blob and be really boring, or do you try and ... you only have a certain amount of opinions and lines. I don't know how to do it. I've never got the knack." This would seem slightly disingenuous, since she has been a regular interviewee for at least 21 years (she is now 40, and mentions it often). The last year has included promotional appearances all over the world, including a depressing tour of America. Yesterday she binned a half-finished manuscript because it wasn't good enough; this morning she started a new one. This, she says wearily, will be her last interview for two years.
Back at the beach, the teenage Kathy Lette was embracing feminism. "We heard about Germaine Greer and thought we could be as sexually liberated as men, without realising that they were all laughing all the way to the sperm bank. Free love meant they didn't have to pay for anything. You know that Germaine Greer is now rhyming slang for beer in Australia? Nobody knows who she is. They just say, 'It's your turn to get the Germaines in.' Isn't that sad? She'd be mortified if I told her."
Having done my homework, I already know that the surf boys were bronze- limbed, blond-haired and blue-eyed, and that she and her friends used to cut out their boyfriends' names in paper, tape them to their abdomens and bake in the sun, so that "if I ever have a melanoma it will be called Bruce". I challenge her to come up with something spontaneous and new. "They had terrific bodies, but they were the sort of men who thought sitting on the toilet was a leisure activity... the sort of men who think sex drive is doing it in the car" Sorry, heard that one. "No, but I've worked out why that is. Because there's that little sign on the rearview mirror that says: 'Objects in this mirror may appear larger than they are.' That's new. You can have that."
Lette became a playwright, columnist and television presenter in Australia until somebody in Los Angeles read Girls Night Out, her collection of short stories, and offered a place on a sitcom-writing team. "It was great training. Nine Jewish guys and me locked in a room. Can you imagine how much fun that was?" They wrote The Facts of Life, a popular teen sitcom, with a cast of actors who had been together since they were nine. "They were unbearable. Their egos were visible from the Mir space station."
Disenchanted, she returned to Australia, where she was still enough of a star to appear on a television chat show whose presenter was Geoffrey Robertson, an international human-rights lawyer with a Clive-Anderson- style sideline. He was 13 years her senior, and lived mostly in Britain, but they fell for each other immediately. Kathy Lette's books contain so many loving descriptions of gold-digging women that I can't resist asking if she was one. Her answer comes with whooping, soaring shrieks of laughter. "I don't believe you said that. You think I was marrying up? Ha! I think he was. That's really funny. Geoff's from the western suburbs of Sydney, and in our Sydney hierarchy I am like a goddess, a princess, because I'm a surfie girl and a first-fleeter. We have inverted snobbery in Australia. If you can trace your origins back to the first fleet ... I'm like royal family, I am the Princess Di of the Antipodes. You didn't realise? You should be down there grovelling at my feet."
She moved to England with Robertson, a move which gave her rich material for Foetal Attraction. "People were spectacularly rude when I first arrived, in that very English way. I thought, 'I either go mad or I get my revenge.'" The novel crudely but successfully satirises a certain metropolitan stratum of the English middle-classes.
We have, she says, a condescension chromosome. "There's a dichotomy in the English nature: you graduate from Oxbridge in Advanced Condescension, but then, whenever someone does a survey about where Poms want to live, 99 per cent want to be elsewhere. You have great misgivings about your national identity."
We're not all Oxbridge snobs. "That's true. When I say things about the snobby English it really is just London English." Hampstead English, even? "Possibly. When I arrived here I did arrive in the middle of the literati."
That's for sure. Jilly Cooper adored Foetal Attraction. Glenys Kinnock called it hilarious. Ian Hislop said his wife laughed so much she gave birth. Salman Rushdie said Mad Cows cheered him up. They were all duly quoted on the paperbacks. It would be churlish to suggest that they only read the novels because they had met Lette at parties with her radical husband. The truth is that famous people loved what she wrote; as did hundreds of thousands of ordinary ones - the sort that a producer of Mad Cows has rather sniffily described as "secretaries, nurses, shop assistants".
Lette was angered by his comments, which patronised her readers. She may be rich but she still thinks of herself as an egalitarian Aussie. Her house is big, but not extravagant, a 20 minute walk away from Hampstead station past traffic wardens who fight class wars in their heads as they slip tickets on to BMWs. The property values fall fast as you cross the Finchley Road. "Where we live is on the groin of so many places. To your posh friends you can say it's Hampstead; to your Labour Party friends you say it's Kilburn; and to your snooty, upper-class friends you say it's St John's Wood."
It's also home to the sort of Australian celebrity that likes to be comfortable but discreet. Barry Humphries lives around the corner, and I saw Natalie Imbruglio in the street. The red leather sofas and polished wooden floors in Lette's home demonstrate privilege, not ostentatious wealth.
"Our kids are in state school," she says. "They're at Fun With Music right now. Sounds so twee, doesn't it? They're in a little church hall doing music stuff. I feel so guilty they can't be outside all the time, at the beach. We're conquering the Great Indoors." Her husband is "at chambers. Saving the world. Doing what he does."
They plan to stay in England. "I've kind of got very fond of it now, in a warped way. The ruder I am about the English, the more chat-show invitations I get. You're very masochistic. You are the only population in the world that had a revolution and then asked the monarchy back."
She did entertain fantasies about being Australian president, until her country chose not to reject the monarchy. "I was practising my profile for the postage stamp. Getting licked all day, that's what I call job satisfaction. I could do a job-share with Geoff: he could do the deep, serious human rights stuff and I could do the shallow one-liners."
At least one of their friends could have offered sound advice on how to act like a president. The couple have known Tony Blair since the days when they lived close to each other in Islington, and often dined together. "We were neighbours, you know?" She seems uncomfortable about "all this power-couple stuff that people write" - then tells me that her husband is working on a new constitution for East Timor. So when was the last time they cosied up with Tony and Cherie? "I can't remember." She is on her feet now, almost squirming. "I haven't seen them for ages. I saw Tony at the conference. That was all. They're far too busy to be schmoozing with the likes of moi."
In any case, she argues, Mad Cows is a send-up of New Labour. "Maddy [the heroine] goes to mother and baby groups in those suburbs like Highbury that are nudging up towards the housing estates and trying to gentrify them. It satirises all those women, those mothers, all those do-gooders, those Porsche-driving progressives who are about as relevant as a 'Free Nelson Mandela' T-shirt."
It seems a good moment to ask what she drives. "I hate this," she says, still smiling. "It's maroon. That's all I can tell you. And I drive a very hard bargain." That rings true. Kathy Lette, professional Aussie, bestselling novelist, Queen of Quip Lash and housewife superstar seems like a woman in control. Or maybe it's just the Kaa eyes.
On my way out, I pass a maroon Mercedes. 2