Mick Jagger, a mysterious brunette and their late-night conversations

Mick Jagger with the Herald on Sunday's Rachel Glucina

So Mick Jagger is lying on the couch beside me in his enormous Auckland hotel suite. He's wearing socks - bright yellow, scare-the-horses socks.

"Mork and Mindy yellow," I suggest. He laughs his deep, horsey, sexy laugh. The night before they'd been black with hot pink and green stripes.

"I love loud socks," he'd said then. At that moment, I loved them, too.

I'm stretched out on the couch next to the most famous ladies' man in music, discussing art and Arsenal, the Kiwi cricketers in South Africa, girlfriends and marriage contracts, drugs and Chinese politics. It's surreal, but also bizarrely normal.

"I've got something special for you, Rach," he says, excitedly, dashing off to bring a bottle of Marlborough chardonnay he'd organised for our last night in this suite. Yes, I spent four fabulous nights with the legendary Mick Jagger - but it's not what you think. Sure there was copious amounts of flirting, numerous bottles of French champagne and lots of late-night laughs - but that's as rock'n'roll as it got. Well ... almost.

Was it easy be-friending a Rolling Stone? Not exactly. There was the burly bodyguard in a bulletproof vest I met the night before the band's Auckland gig last Sunday who said he was on the look-out for "prowlers".

"You know," he explained, "paparazzi, journalists and young women who want to meet Mick and get their picture in the paper." Oh God, I panic. I'm all three of those.

We're sitting in the lobby bar of the Langham Hotel, where Mick, Keith, Charlie and Ronnie had arrived two hours earlier. I'll be honest - I was on an official undercover stakeout for the Herald on Sunday. Perhaps I might catch Mick flirting with a pretty girl. Maybe I'd see someone drink too much. Take drugs. It's gossip, not rocket science. There are 385 people in the Rolling Stones entourage and crew - something had to happen.

Just after midnight Mr Jagger makes a low-key entrance into the bar - the others, I later learn, prefer to party privately in their rooms. "They've got wives and family," it's explained.

My girlfriend and I stay to drink Bollinger Reserve with the entourage while Mick is two seats away and, though I never get to speak to him, it's all terribly exciting.

Next day, the bodyguard - Paris Hilton's former protection - calls. Nice to have met me, he says, and would I like a couple of VIP tickets to the concert? We could catch up afterwards. At Western Springs, I get a text wondering if I'm happy with the seats. Happy? I was a personally-invited guest, sitting a handful of rows from the front and I'm partying with the Rolling Stones later. Happy was an understatement.

Back at the hotel bar, post-concert, Jagger's bodyguard whisks me aside and whispers that Jagger would like to come down - would I mind sitting and talking with him? "He likes pretty girls," he winks. Within minutes, guests were turfed off a couch, chairs had been drawn up and I was being beckoned to sit and await His arrival. Beside me is my undercover sidekick, Olivia Hemus, former model, social photographer, a snappy little camera sitting pretty in her bag. We wait.

The wiry man in the disheveled shirt and jersey around his shoulders looks little like the rebellious, arrogant, peacock showman I'd seen earlier on stage. He meanders around the bar then lounges on the couch next to me. And so the fun begins.

Mick Jagger is a talker and the banter never stops. Was the Easter bunny good to him? It was better to his kids, as he'd sent luxurious chocolate eggs all over the world.

"I have seven bloody kids," he laughs. "I could have my own basketball or volleyball team." He brags about his lavish holiday home in the Loire Valley, where he goes to "relax and unwind, though all my friends like to holiday on the Dalmatian coast at the moment". Vacation name-dropping. Bless. I'm impressed.

There's no doubt Jagger loves the company of women - young women particularly. He is an incessant flirt, but charming with it. And there is that Peter Pan complex. He's smitten with our youthful enthusiasm and likes a bit of attitude. Though there is a universe of difference between our lives, he'll compare his various exploits with mine. On my New York travel tales: "Oh yeah, the Chelsea Hotel. I used to visit Dylan when he stayed there but that was before he made his money."

Mick is nothing if not cool but there's still an appealing vulnerability about him. He's theatrical and tactile; he recoils into his thin frame, crossing his outstretched arms across his chest.

He commissions Alexander McQueen and Dior menswear designer Hedi Slimane - master of the thin androgynous look - to make his stage costumes. "I'm getting new ones from Hedi when I get back to Europe," he says. "But I always have to stipulate to him not too thin, I have to be able to move on stage."

He calls the waiter for more champagne. But not for him, he's on water. "Three's my limit and I've guzzled them back already tonight."

And that is just one of the surprises about the debonair but disciplined Mick Jagger.

Over the next few nights, I learn that the man infamous for sex, drugs and Marianne Faithfull never touches cocaine because he can't keep up that lifestyle anymore. He bought champagne for us but won't touch the stuff himself. He hates the bubbles.

His thirst, these days, is for good conversation, a good workout and his own creative work. But that's not to say he doesn't like a laugh. We're sitting side by side on the couch and our thighs are touching.

"Oh my God," I shriek. My thighs are twice the size of his.

He roars with laughter.

He hates going out with people who don't eat. Karl Lagerfeld, he says, never eats.

Despite that tiny frame, I can attest that Mick Jagger eats. Though he spent the next three days in Wellington ("are you coming?" he'd asked - like I was a bonafide groupie. But no, I had to work) his bodyguard rang on Wednesday night to say Jagger would like to go to dinner. We went to Cibo (he makes the booking under the name "James") with Olivia and Victoria, the Welsh woman who runs his LA film production company. The rock star ate quail salad and duck confit - and most of my chocolate dessert.

He drank merlot, sparingly, and water. We talked about, well, tabloid journalism. Jagger's making a film about it and he reckons Rupert Murdoch is worse than George Bush. No accountability, apparently.

Mick knows that I own a marketing company, but he has no idea of my other job - for the Herald on Sunday. Olivia has told him she's studied photography. And, thankfully, he doesn't hate all journalists. Mick prepared for last month's historic tour to China by ringing his old mates to ask what he should know about Chinese censorship.

"I rang Bill Clinton for some advice on what to say to the media," he says. And then he was miffed none of the Western journalists were interested - they just wanted to know what songs he'd had to cut. "I don't care [that the Stones had to cut four songs] - we've got 400 to pick from!"

Mick has flown back to Auckland to film a cameo role in an ABC comedy pilot - the rest of the band, he says, has scattered. "Ronnie's gone to Fiji - he keeps calling himself an Islander," he laughs. He cannot understand why the Americans in the entourage flew straight back to the US. Mick wants to travel - he once ate raw puffin meat in Iceland and is off to Cambodia and Laos with his backpack and Lonely Planet guide for the next two weeks. Daughter Elizabeth, he confides, is holidaying in New Zealand with friends. One of Mick's holiday homes is in Mustique and a rave about the West Indian diet becomes a conversation about Type-2 diabetes and Maori.

Olivia, the undercover photographer, requests a snap. Jagger refuses. He confesses he's been burned recently by a woman he met in a hotel lobby. She wanted a picture with him. He obliged, and found himself front-page news and in a supposed relationship. Olivia begs, saying my mother would love to see it on her birthday next week. Jagger relents, a bit. "Oh sweetheart, let me write your mum a note instead, eh?"

Jagger's paranoia about girls is well founded. There has been the long, long list of lovers and wives and one-night stands but Jagger is still a romantic. He talks about the "beautiful little church in France" where he married first wife Bianca but says, without irony, that people don't always realise the significance of a marriage contract.

"There are two legal contracts - one to your partner and one to the state," he says. Business contracts are more his thing, these days.

On Thursday my phone rings at 11pm. "Hi Rach, it's Mick," he says. (Ohmigod, Mick Jagger just phoned me.) We had planned to go dancing but Mick's tired after filming. Would I like to come over to the suite? "I'm under Mr Cameron."

Tonight he is at his most relaxed. There are those yellow socks (topped by extremely tight grey trousers) and he's jovial, proud he chose wine he thought I'd like and keen to know if I can pick its region. His bags are packed for Friday's flight out, Sade's latest song is on his iPod and he's joking about the differences between his many children.

When Georgia was 9, he tells us, she insisted on going to his local cinema to see the Spice Girls' movie. Jagger didn't want to go but his daughter won. And when she wouldn't carry her soft toy, Spot, he did. "She goes 'oh Dad, I can't be seen walking in with Spot', so I have to walk into the movie carrying a stuffed dog."

He obviously loves his kids, but he doesn't mind poking a bit of fun. Will they reciprocate? "Oh yeah," he says. But his second wife Jerry Hall cops more. The kids aren't always enamoured with what Hall wears, telling her she 'can't go out dressed like that'. Jagger says he tells his former wife she should wear what she wants.

Hall this week told the Daily Mail in Britain that women should stay away from rock stars.

Me, I'm glad I didn't. Sure, Mick didn't know about my other job, writing for this paper. If he had, chances are my four nights would have been barely four minutes. But the subterfuge was necessary to meet the real man, to find out what a famous rock star is really like.

Jagger was simply the most fascinating man I've ever met. He's sexy, intelligent, learned, enormously funny and passionate. He also never laid a sensual hand on me; always the perfect gentleman, even thanking me for the fabulous time together.

It's 2am now and we're tired. Mick hugs and kisses me goodbye and invites me to visit him in Europe this summer. "Ooh, I'd love to," I confess. London and the Loire Valley, I dream. And wouldn't that be the most perfect follow-up story? ..