It's 9 p.m. It's Friday night and school's out for the weekend. Monday morning is a lifetime away and a B*witching night of boyz, spice girls and playing that song so loud - 'Cos we want to! - lies ahead.

The night is young. But not as young as this lot.

Old Wesley RFC disco, in Dublin's Donnybrook, is the only place to be for many a discerning 14- to 15-year-old Dubliner as the weekend beckons.

The epicentre of Donnybrook, salubrious Ballsbridge and the embassy belt by day, this otherwise innocuous strip of Dublin's southside - the Donnybrook Road - is for four hours every second Friday night the domain of the teen dream - an unabashed fest of Betty-boop dresses, Tommy Hilfiger jackets, space shoes, short, shiny skirts, boobtubes, sparkling hair and glimmering hormones.

As a 10-year-plus graduate of the Friday night expedition to Wesley - when this reporter and other Ranelagh-based mischiefmakers would venture out while parents thought we were "watching TV in Hughie's house" - I know well the resilience of the bonds made by 14-year-olds on illicit trips to Wesley's hallowed dance-floor. They are bonds never broken.

And bonds of a sort are being made on this Friday, at a corner just beyond the Spar store.

"She drank vodka and now we've been kicked out of the queue," two irked figurines explain, a helpless companion falling about, rag-doll-like, in their arms. "I think we're going to put her in a taxi home. Her mam will go mental. She's 15," one continues, "and we're both 14."

Dressed in tight, velvet pedal-pushers, a short, sleeveless, sequinned top and high, strappy black sandals, the other proudly explains how she achieves the tiny clusters of silver stars on her cheek bones, just beneath her eyes. "You get it in Miss Selfridge. It's called glitter pot. "I suppose I had my first drink when I was about 12," she says. "We wouldn't drink here, though. You can't get in if they know you've been drinking."

Further up, towards the gate, a 15-year-old bounds about greeting friends, strangers and anyone who will accept her declarations of love. Dressed in a pink leisure outfit and trainers, with her blonde ringlets tied casually up behind her little face, she hops from side to side. She reveals that she has been coming to Wesley for three years.

"I'm friends with all the bouncers. I don't wear all those glamorous clothes because I'm too old now - I go natural." Having spotted three lads, she trots off to hug each before dancing into an embrace with one of the security men on the gate. "Hi," smiles the bemused bouncer. Once past the vigilant bouncer, the next hurdle is the queue. The average wait to pay the £6 entrance fee is 40 minutes. To survey the owners of micro-mini-, sleeveless-dress and open-toe-sandal-clad female limbs, in a biting 3 C night is to witness the true meaning of il faut suffrir pour etre belle, or at least . . . pour etre une fille de quinze ans Dublin-style (the young men seem to kit themselves out in warm uniforms of Ben Sherman shirts and Levis).

But hey, it's worth it. There's nothing, for a young person in the first flush of adulthood, to compare with the anticipation of four hours of their music, their screaming, their flirting and their heart-breaking, all in a space where no parent dares to tread.

"Say you will/Say you won't/Say you'll do what I don't/Say you're true/Say to me/C'est La Vie" thumps a throbbing Celtic pop beat once into the hall. Shoulder to shoulder, kids belt out every word in unison as they hop, pop and jerk about to the beat-happy B*witched single. Ecstatic cheers go up within three seconds of the next disc's spin. "Do you believe in life after love . . ." chants Cher, and they all chant with her.

On benches around the hall are youngsters variously taking a rest and going (nervously? enthusiastically?) through those excruciating young motions of "getting off" with others. Couples on the dance-floor are determinedly oblivious to the exuberant bedlam around them as they too get, literally, to grips with each other. Hands wander, but as an old Wesley hand explains: "If people go too far they get kicked out." Most of the girls are tiny, their little, thin arms and bony elbows veiled in dresses which look more like underwear than real clothes, or short skirts and camisole tops. Bra straps are proudly evident. The males are an odd mix of young men with the first signs of facial hair and breaking voices, and boys, awkwardly aware they look perhaps just 10 or 11 years old. Corinne Huet, a sallow-skinned, sparky young thing, is 15. She has come with her friend Tara and is anxious to be quoted extensively. "We meet up in one person's house and it takes us about two hours to get ready. Then we come here on the 46A bus."

Tara says there are no "good discos" in Foxrock and that she buys her clothes in Top Shop. Dressed in a short, red dress she got in Kookai, she says she likes going into town on Saturday afternoons with her friends, shopping and hanging around Grafton Street. "I like Mac make-up from Brown Thomas. Yeah, it's expensive, but you know - you have to pay for beauty."

Corinne is sorry the old DJ has gone - John Power has been snapped up by 2FM. "He was soooo yummy," she says. On dressing for Wesley, she says: "Discos are all about exposure." Others have come from the other side of the city. Gary Doyle, from Coolmine, is 15. He has come tonight with 15 friends: they hired a minibus for £4 each.

"Ah, you hope to find a girl maybe, but mainly you come to have a good buzz with your friends. It's the best disco, Wesley. It's deadly."

In the ladies' toilets a heart has already been broken. Ana, inconsolable, is being comforted by friends Jessie and Isobel. Her blonde waves of shoulder-length hair are clipped elegantly; short, grey skirt is slit a little way up her thigh; small, black T-shirt shimmers with a mirror design and black, suede boots reach just beyond her knees - but all for nothing because the guy she really, really likes thinks she stood him up.

Wiping tears from red, puffy eyes, Ana says she is "really upset". She just feels like dying. "He told me he wasn't going out with me any more."

The tiny Isobel, a schoolmate, has a short, shiny bob, sparkling eyes and an infectious enthusiasm for the moment. She is diverted from her comforting duties, delighted to be talking to "a real reporter, like". "I got my lacy number," she says, perkily referring to her camisole top, "in Miss Selfridge", and just as suddenly hops one step back, looks to her two friends and, hands on hips, exclaims: "God, we should be out dancing." Lorraine Hopkins is the longsuffering woman who keeps an eye on the ladies when there's a disco. "I make sure the toilets stay clean and that no-one is drinking, and I look after the girls. They come in here upset about boyfriends, or upset they've just got a love-bite, wondering what they're going to do to cover it up."

There are about 15 staff on each night - between security, the cashier, staff at the refreshments bar (which sells cola and chocolate), the cloakroom staff and Doney Bolger. Bolger runs the disco for Old Wesley, which has been going now for over 15 years.

"Wesley is almost a rite of passage for many Dublin kids. It's their first experience of socialising as young adults in their own right," he says.

Alan Chapman, spokesman for Old Wesley, who drops in on the disco from time to time, says the thing that comes across to him most of all is the "pure innocence and excitement of the kids". Drink and drunkenness are conspicuous by their relative absence on the Friday night The Irish Times takes to the dance-floor. Because it is just after Christmas, it is said to be a relatively calm night. Apart from the scene outside earlier, just one incident of drunkenness passes my path.

However, as Chapman concedes, there have been problems, with local residents complaining about drinking. A spokesman at Donnybrook Garda station said that for more than a year, after complaints from residents on nearby Anglesea Road, two gardai have been assigned to patrol the area on Friday and Saturday nights "to make sure the kids go home and aren't hanging around".

"The complaints have been about drunkenness and general bad behaviour," the garda said.

The high level of club security and efforts to stop, as far as they can, drinking on the premises are at least partly attributable to good business sense. Complaints might close the disco down and the discos, Chapman says, account for about 30 per cent of the club's income.

By midnight a fleet of cars has pulled up on Donnybrook Road, each with one adult - a parental chauffeur - within. Jimmy Kennedy from Ashbourne Road is waiting for his 15-year-old daughter, Alice.

"This is her first time at Wesley, though she's been to discos around home. She's a good young one, but of course you worry, mainly about drugs," he says before asking what it's like "in there".

Carmen Cassin from Beaumont is waiting at 12.30 a.m., to pick up her son Niall and his four friends. "Well, they don't tell you what goes on at the discos, really. You just have to trust them," she says. "They have to learn and make their own mistakes, because they certainly aren't going to listen if you try to stop them. But the main thing I'd worry about is drugs. The thing is that there are so few places for them to go to at their age."

Back inside the gate, three Sandymount girls are getting dressed. Debby, aged 14, is pulling tracksuit bottoms and a sweater over her mini-skirt and T-shirt. Off with the heels and into the runners. She's walking home with friends Antoinette, Louise and Edel, each now suitably attired for sub-zero Dublin. "It was deadly. Loadsa fellas. I got off with three," declares one.

And as we wander off in our separate directions, I can't help but think of Hughie of the TV alibi, now working the New York stock market, and whether to be sad that I have almost certainly just left, for the last time, the ever-optimistic, ever crazy and ever-young Wesley disco.