Davinia Taylor is in her downstairs loo. “That’s Kate and me just after we left Disneyland,” she says, pointing out photos. “And there she is in the country, washing the car with Lila. Oh, look, the Duch!” - the Duchess of York, on a night out with Princess Eugenie. Here is Davinia with her new baby, the now 11-month-old Grey, and her husband, David Gardner, the footballer turned agent and David Beckham’s best friend. Next up is Mick Jones in a dinghy - “He could not believe,” she roars in her deep Wigan accent, “that he was in this stupid little boat!” - then a snap of Jake Chapman’s daughter in a highchair, the word ‘F***’ artistically picked out in raisins in front of her. “She didn’t do that herself, obviously.”

Ah, the inner sanctum. Along with Kate Moss, Sadie Frost, Sienna Miller and a host of other party animals, the former Hollyoaks actress has been a core component, if not the driving force, of “the gang” for more than a decade. She met Kate “years ago. It’s the same party scene, isn’t it? You kind of click and that’s it. Like goes to like”. Together “they’re like sisters”, says the hairdresser James Brown, himself a long-time member. “It’s always giggly, like little girls. It’s not a bitchy crew: we’ve all been friends for a long time. It’s like the Waltons, the psychedelic Waltons. Everyone really gets on.”

Well, they’ve had to. A colourful collection of pleasure-seekers - “young, rich and beautiful”, says Brown - the group has weathered some of the most thrilling scandals of the tabloid era. The break-up and subsequent affairs of Sadie and Jude Law; the Cocaine Kate allegations; the Pearl Lowe wife-swapping saga. Davinia herself has been in the hot seat several times, once for an alleged lesbian threesome with Kate and Sadie, and a kiss-and-tell by Barry Smith, one of Sadie’s toy-boy lovers, who claimed that Davinia had cheated on her husband with him. “There’ve been a lot of nasty lies written about me,” she says.

Davinia herself hasn’t given an interview in years, so it’s rather astonishing to be here, crammed into her loo, hearing tales of boisterous parties, compulsive house-hopping and the time Kate lived downstairs, after she broke up with Pete Doherty. “He’s way out of our lives now,” she says tensely. Living with Kate must have been great for her wardrobe. “But I can’t borrow anything,” she sighs. “The only thing I fit into is maybe . . . a bag. Not even a shoe - she’s got size-three feet. She’d lend me anything but it just won’t go on.”

These days, they spend most of their time in each other’s kitchens. “A good night out is a night in for me,” says Davinia. “You go out to socialise and once you’ve found your clique, you stick with them. They know all the stories, the tribulations, dramas . . . you don’t have to go over old ground. It’s just about having fun, a good old chinwag and a heated debate.”

This on-private-premises lifestyle means that, to the outside world, the Primrose Hill set has always seemed impossibly inaccessible. Did it nearly break up when Davinia sold Supernova Heights to David Walliams three years ago? “Are you insane?” says Davinia, swishing into the newly appointed kitchen of her seven-bedroom house in St John’s Wood, a place she calls “Club Kitchen”. “This is the new Primrose Hill. We’ve all moved, en masse. Kate’s 35 seconds down the road; I jog there. I jog a lot. To the pub. To James Brown’s. To Sadie’s. [When I lived] in Supernova Heights, she was right opposite. I used to go to Sadie’s in my pyjamas with a bottle of – actually, who am I kidding? - a box of wine!” She only left Supernova because “I couldn’t cope with the stairs. I kind of miss the larger garden now that I’ve got the baby. But I just wanted to move out”. Then she bought the current place. “I saw that pub, saw this house,” she says, “and then I had a mass exodus follow me.”

At 30, Davinia is good-looking, glossy and blonde, with a rich-girl’s tan from the weekends at her mum’s place outside Marbella - “not the tacky part, though”. She has a new asymmetric haircut, chopped by Brown (in whose hair-care range she is an investor) during one of her Club Kitchen dinners using the kitchen scissors, no less - “like Ginger from Casino. I’m doing a film in August set in a casino, but in Wigan, where I’m from. It’s perfect”. With her husky voice and petrol-driven cackle, she’s a Wag version of Oliver Twist’s Nancy - strident, up for a laugh, the person most likely to scream, “All back to miiine!” She would make the most perfect pub landlady.

“I’m giddy, really,” she says. “Quite young in the head. Very easily led.” As an actress, she says, she “does a great bitch”. Indeed, witness her as the conniving Jude in Hollyoaks: “She started off as a really conscientious student,” she laughs in disbelief, “but when they got to know me, they were like, ‘Let’s turn her into an alcoholic bitch turned prostitute.’ ” The house is beautiful: pin-neat, with dark walls, antique rugs, dramatic wallpaper, and taxidermy everywhere, including a parakeet that lost its bell jar in a drunken accident. There are Banksys on the walls (one from Sadie). A typical northerner, she’s “very house proud”. She cooks for the gang “five times a week. Ring round, see who’s in. We’ll chat about fashion, food, friends, what they’ve been up to, what everyone’s up to next week. Planning adventures. Kids. Normal chitchat, like you’d see on Coronation Street”. She’ll crack open a bottle or seven from the walk-in fridge (“ Never enough booze”) and rustle up a “Sunday roast with loads of kids. A chicken and a lamb - I’ve got two ovens”. She is particularly proud of the dinner she once gave for Rhys Ifans, “possibly the funniest man on the planet. I did a crab tower and everything. He was like, ‘Babe, this is so lovely’ ”. Eventually, she’ll boot everyone out. “Sometimes, because I’ve got a couple of spare bedrooms, it’s the day after. ‘We’ll stop here tonight.’ I like the company.”

Upstairs, Grey’s bedroom is a haven of cream. “I’ve got the most unbelievably placid child,” she says. She “nicked the name Grey off Mario Sorrenti”; David Beckham and Kate are rumoured godparents. “People cannot believe that two such mental, het-up, argumentative nutters have this angel of a child,” she says. She can’t really bear football, so her husband’s footie regalia (including a kit signed by “Uncle David”) is firmly relegated to his office in the basement, “the dungeon” where Kate and Lila stayed. “We took the cooking in turns,” she says.

Worra life, eh? All her friends say she’s very happy, and with a thoroughly pleasant husband (“Saint David”), a tight group of “high-profile and old schoolfriends” and a beautiful baby, why not? Clearly the family money helps a bit, but she appears largely unspoilt by her wealth, perfectly happy to plod off to Primark with Grey in the buggy. A tireless raconteur – accents, anecdotes, physical theatre, the lot – she is brilliant to spend time with. Much like her father, one imagines, whom she describes as “a genius businessman” and “hilarious Scouser”. Dubbed the “Loo Roll King”, Alan Murphy (Taylor is Davinia’s mother’s maiden name) amassed his £200m fortune from supplying paper to factories. (One of his yachts was called La Naturelle Dee, after his top-selling roll.) This weekend, it’s his 60th birthday, which he’s celebrating at home in Monaco. “I’m taking my friends for backup,” she chortles. “Load up the jet, take the yacht out. There goes Monaco.” An only child, she was largely unaffected by her parents’ divorce when she was 20, and her father now has a girlfriend, Wendy. “They’ve got a baby, so basically my dad’s son is Grey’s uncle at the age of two.” She doesn’t mind her heirhead tag. “They call me the loo-roll heiress,” she says. “I think it’s funny. Loo roll’s recession-proof, for God’s sake. Think about it - when the market fell in the 1990s, everyone was shitting it.”

We decamp to the pub. Davinia is even more at home here than up the road, putting away a double vodka and tonic (it’s midday) and two large glasses of sauvignon blanc in under 90 minutes. Also a Cajun chicken sandwich - “with chips!” she roars. “Oh, I’m such a picker. I was over in Paris with John [Galliano, who was designing her wedding dress] and he said, ‘Little pickers wear bigger knickers’ while he was trying to get me into this corset. But I’m ruddy staaarving!” She breaks into a peal of laughter, before going to the back of the pub. “We usually sit in there,” she says, “as they won’t let the paparazzi round, so Kate can relax. Upstairs there are bedrooms . . .”

“Not for you,” says the landlady. “She knows me,” says Davinia. The press always does its best to crash the parties. “I’m afraid so,” she says, referring to the “25,000” paparazzi outside Kate’s home, all day, every day. As for those nasty things they’ve written, such as the lesbian business: “Absolute bullshit!” she explodes. “I think it came from everyone staying at everyone’s house. It was quite slanderous . . .” she tails off. “But you can’t take on the press. They’re a machine. What do you do? Ring them up from your bedroom crying? They’re selling papers. Tabloids are dark. I don’t know how people who do that sort of press sleep with themselves. It’s not right.” She pauses. “It’s money. Money, money, money.”

Inevitably, personal relations suffer. Not everyone has survived “the gang”. Pearl Lowe famously crumbled under the pressure of their drug-taking, eventually moving to the country to escape it all. “There was a general belief in our world that you couldn’t have fun unless you were slightly out of it,” she said. But, “put down the drugs and you don’t have much in common. What I did miss initially was the quantity of friends, the constant phone ringing, the ‘what are you doing tonight?’, that sense of being in a gang”. When Barry Smith sold his kiss-and-tell, Davinia’s marriage was rocked. But she maintains that is behind her now. “The only people it hurts are your parents,” she says. “They don’t want you to look bad. It’s tomorrow’s chip paper and everything, but when it’s in their head that something’s going wrong, they worry. They’re like, ‘Are you sure you’re boiling that egg right? Are you depressed?’ ”

She spends a lot of time with her mother, who now runs Mya, a cosmetic-surgery clinic, and who brought her up like a princess. “I think I was three or four when I ordered my first escargot and lobster. The waiter just went, ‘What?’ ” she chuckles. “I’m a big foodie. It’s my thing.” Her mother used to cry every time Davinia went off to boarding school. A curious mixture of naive (she was the last girl in her year to kiss a boy) and party animal — at 15, her favourite occupation was “to climb out of my bedroom window and go to the Haçienda” — she landed a part in Hollyoaks straight out of school. She left after a couple of years, amid rumours that she had been sacked for poor timekeeping.

“Not true,” she says. “I left! I’d filmed the final scenes. The producer simply wanted the last bit of publicity. She was a bitch, so I threw a glass of water over her head and stormed out.” She pauses. “It’s damaging for my career, which isn’t fair. I bumped into her once. She had some stupid ensemble on. I said” — she wiggles her finger through the air — “ ‘And what are we wearing here?’ She went bright red. That’s how you get to a woman. You go, ‘What’s this, then?’ ”

Davinia married David five years ago after a string of boyfriends — Ryan Giggs, Nellee Hooper and James Gooding, to name a few. “We’re madly in love,” she says. “He’s so nice, isn’t he? He proposed on a swing. I was like, ‘Waaah!’ Textbook stupid woman. Six months later, we were married.” On her finger — scratched from trying to open one bottle of beer with another — is a huge sparkler. “I’ve thrown it at him a few times.” Initially, he wanted to live in Cheshire but after six months “it was like, tap, tap, tap” — she drums her fingers. They moved to London. “I think his eyes got opened rather wide. He was like, ‘Bloody hell.’ ”

She’s now back to work, with a play on in the autumn (“Urgh. I’m the sort of person to walk off the end of a stage”) and a film in the summer. She wants to try for another baby, but in September, so she doesn’t have to “sit around in the summer like a big, bloated whale, watching everyone having fun and not even being allowed a shandy”. She wants to take James Brown’s range “international!” and see more of her younger friends, who include Princess Beatrice and Kelly Osbourne, who bought her a platinum whistle for her Haçienda-themed 30th last November. “Kelly’s an absolute dreamboat. So stylish. She refuses to go brown, whereas I’m a northerner and like, ‘Sunbed!’ ”

Will she always be a party girl? “It’s better than being boring,” she says. As for memoirs: “Oh no, I can’t remember them,” she laughs. “I wouldn’t know where to start.”

James Brown London haircare available at larger Boots stores. Visit www.jamesbrownlondon.com for further information

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