Suddenly, everything became clear. This was the mothership. The HMS Britannia of some parallel universe, setting sail for the wilder shores of altered states with a truly loony crew as the event horizon of Hong Kong's handover loomed into view. This was frantic fin de siecle fantasy, escapism and hedonism, utter nonsense that made perfect sense. It was the best of times and the worst of times, the alpha and omega, the ecstasy and the agony, the soaring high and the crashing comedown.

For the 'FILTH' ('failed in London, try Hong Kong') crowd, the chancers, the gifted gabbers, the wide boys and barrow boys, the restless souls who had fled comfortable middle-class lives for a great adventure and a fatter pay packet, and even for a wide-eyed naive Brisbane boy like me, this was our Woodstock, our punk rock, and we knew it.

To the north was the Motherland, and we all knew winter was coming. But for a brief season, Hong Kong's 'summer of love' reigned. We had found the glowing magma core of the barren rock.

This was Planet Neptune.

It was dangerous ground; shifting sand. I had gone to Jimmy's as an objective reporter intent on covering the story. At some point in the proceedings, I crossed from observer to participant - 'sorted and on one', as Ravey Davey Gravy of the adult comic Viz might have said.

My journalism and raving careers might both have ended right there - a friend close to the Hong Kong Stadium's management at the time (Jimmy's was at the stadium) told me recently that a big undercover police operation had been planned for that night. The DJ playing was Graeme Park, avatar of Manchester's Hacienda club, where almost a decade earlier another 'summer of love' had seen decorum and common sense subsumed by glow sticks, yellow smiley faces, synthesised beats and chemicals.

Apparently, stadium staff tipped off the dealers and ravers, pooping the party for the police. My clumsy attempts to score went undetected. That first party passed in a gurning blur and a serotonin tsunami as methylenedioxymethamphetamine and music rewired bits of my brain. I followed the swirling crowd to Wan Chai and kept hearing the same murmured mantra: 'Neptune'. Then it was down the rabbit hole and into a world where time played tricks as exotic Lamma ladies twirled glow sticks in pockets of ultraviolet light.

Sparkling cascades of piano were washing over the crowd. 'The time is right,' a gospel vocal gloated, 'for ecstasy all through the night.' It was about 5am, and the helpers were leaving to get ready for church. But this was church, and God was a DJ. Hands waved in the air. Something spiritual was happening, however fleeting or artificially induced.

No one cared what you did for a living, or how much you earned, hot topics of conversation in most other Hong Kong nightspots. Neptune was egalitarian, an ego-free zone where the act of surrender was the great leveller.

Later, I would get to know the congregation. Among these shirtless shape-shifters were stockbrokers and construction workers, bankers and sandwich sellers, blaggers on the make and airline pilots on acid, English teachers and engineers, dreadlocked crusties, smiling triads, Hello Kitty cuties, mad-for-it baggies and buttoned-down preppies.

I'd also meet the priests, for Neptune was a tale of two DJs, a parable of two talents on unexpected trajectories. Affable Englishman Lee Burridge, lanky and often grinning, and glistening Eurasian Christian Berentson, whose pretty boy looks, aloof rock star aura and distinctive mixes earmarked him as a superstar DJ in waiting. Fate had other ideas: Burridge parlayed his Neptune cachet into global DJ fame; Berentson stayed tethered to Hong Kong and his close-knit cadre of party animals and acolytes.

Irvine Welsh was writing about riding 'a rocket to Russia', even as Danny Boyle's film of his masterpiece Trainspotting was packing Hong Kong cinemas. I saw it three times in a week, enraptured by its rave scenes.

Everybody in the room that night, and on the 200 or so Saturday and Sunday mornings that marked Neptune's doomed, dizzy orbit, was taking the ride at different speeds. Eventually, economics and physics cut through the chemistry: the law of diminishing returns, and the hard-won knowledge that what goes up must come down. For some, dark places and demons lay in wait. A few would not get out alive.

As the 15th anniversary of Hong Kong's handover draws near, almost 400 people scattered around the globe have been reliving their membership of a club that has now passed into legend. Some of them were dancing in Neptune, much as Nero fiddled, as the PLA marched across the border. More than 200 of them, myself included, joined a 'secret' Facebook group so the incriminating photos and stories could be posted and savoured, the casualties remembered and the bacchanal's soundtrack - the tunes, man! - celebrated.

Here are the stories, in their own words, of some of those who were there.

Arrival

Lee Burridge, DJ: 'I came in 91. We threw one of Hong Kong's first raves at the Beach Hut in Lan Kwai Fong.'

Christian Berentson, DJ: 'I began a residence at the Big Apple in Wan Chai in the middle of 1993, having flunked out of university in the UK. Lee Burridge was resident across the road, at Joe Bananas, and used to come down after work and spin [records]. We ended up at Neptune because I was fired from the Big Apple - too many long jaunts with Lee to Thailand to play at the Full Moon Party.'

William 'Bill Dup' Corbett, DJ: 'The music was at its peak, there was still variety within the scene, drum 'n' bass and techno and handbag house - stuff that wouldn't have been played together in London.'

Bob Trotter, Ecstasy dealer: 'Having arrived in 1990 straight from the UK warehouse party scene, I found HK a bit slow at that time. But it seemed to accelerate massively. Pre-handover Hong Kong became the new Utopia.'

Burridge: 'The month we started, we were playing to a totally empty dance floor. People were used to shouting 'Big Apple' after the international dance music events [that happened in the city]. One night, though, it just suddenly changed and everyone moved over to Neptune.'

Belonging

Trotter: 'I avoided Neptune for at least six months, fearing it would be tacky. When I finally did go, I was shocked. Firstly, by how busy it was. Secondly, by how many people I knew there. And lastly, how brilliant it was; friendly, messy, banging and, oddly, very safe.'

Jane Fitzgerald, music journalist: 'I was a teenager when the summer of love was in the UK [1988-89], and I do see a lot of parallels - it being a special time, people discovering new ways and possibilities to party together.'

Marco, European expatriate banker: 'Neptune to me meant being truly part of the underground scene. The seedier the place at an ungodly hour, the trendier and more rewarding the whole experience would be. There was something of an iconoclastic ritual to it, which I cherished. It felt like being a member of a secret fraternity or a sect, where class, background and job position had no importance. I was fascinated that many like me could lead a double life: respectable lawyers, investment bankers or fund managers during the day, and drugged-up patrons of seedy establishments at dawn.'

Abby Lai, DJ: 'I really was not the first female DJ [in Hong Kong] but probably a lot of people remember me as such. Neptunes was the place where everyone went after rave parties and the bar scene, where people would continue the vibe of the night and hope it never ended. It was really a happy place; a place for me to relax after DJing at parties around town.'

Stefan, expat British businessman: 'It was more about the promise of sex to me, the opportunity, as much as the music and the drugs. I rode my motorbike down the stairs once, in a desperate quest to make an entrance.'

Anita Buenaflor, real estate agent: 'I'll never forget what happened, the most hard-core party times with the best goose-bumps music - sometimes I get them even when I hear the tunes now. It was cool fashion, non-stop energy until Sunday afternoon. Sometimes on the dance floor it was as if we all just shared the one big heart.'

Burridge: 'Young and old. People who worked late or just loved dance music, staying up late and getting wasted. Hookers, sweethearts, bar workers, triads and normals. It was home.'

Corbett: 'It was the wild east meets the wild west, a direct interface between cultures, you could smell the waft from the melting pot, feel the steam and, if you weren't careful, get seriously burned by the high octane flames.'

Kay, university student: 'I was one of the 'Fluoro Girls' from Lamma, I called myself the 'techno terrorist'. We'd get up at 5am, get dressed up in fluoro gear and get a sampan to Neptunes. It was seedy and kitsch, but Neptunes was a community and it touched everyone.'

Anderson, global fashion brand chief executive: 'I was amazed by the people you met there in global positions of loft. Without those years of Neptune, Christian, all the crazy mates, I wouldn't be half the person I am today.'

Cath Bennett, office worker: 'I have been introduced to friends of friends who have lived in Hong Kong and once you know that they also went to Neptunes, you can skip through the small talk and know that you are going to be pals, that you don't have to explain stuff.'

Highs

Berentson: 'It sounds bragadocious, but overseas DJs, having experienced Neptune, often begged to get a DJ slot there.'

Kay: 'Someone brought [the game] Twister to Neptunes. Keith brought a clump of broccoli - by the end of the night everyone had broccoli attached to some body part.'

Marco: 'I went to the toilet, bare-chested and high as a kite ... [afterwards, I] went to the bar, only to be tapped on the shoulder by someone. The toilet paper [stuck in his trousers] had not detached from the roll but had kept unwinding, like in those adverts where the puppy dog grabs the roll and runs.'

Cecilia, teacher: 'The 4am conferences in my friend's office; we'd leave Neptunes, walk down the road, go into the office block, commando roll under the half-open shutter, past the old porter, sign in to the building register, all of us wearing sequins and glitter. The tin foil, or light bulb, the straws, specially adapted lighters and the ceremony would start.'

Corbett: 'Everything you did during the week was just a precursor to Neptunes, and then the comedown. It was like climbing to The Peak and down again.'

Robin Chappelle, digital marketing consultant: 'The Neptunes era was a period I look back on fondly. It was then I realised my passion for dance. Like a sportsman getting into the zone, there were nights where I truly felt I became one with the music. It wasn't all a bed of roses, but it was a celebration of life.'

Fitzgerald: 'Neptunes is the standard against which I've measured every other after-party since, and I can honestly say nothing has come close to the atmosphere or crazy scenes I saw down there.'

Burridge: 'Drugs were a huge part of the dance music scene in Hong Kong [as they were across the globe]. Here's the thing, though. Lawyers and bankers were doing cocaine in the bars of Lan Kwai Fong. Maids were smoking Ice and kids were out dancing the night away on Ecstasy. We have rules in our society and kids will always want to break them.'

Lows

Dino Smarts, party animal: 'Don't get on the horse if you can't ride a horse and leave the needles on the records.'

Chris Thrall, author of Eating Smoke: 'I left the Royal Marines in the UK to run a business in Hong Kong. A year later I was homeless, in psychosis from crystal meth addiction and employed as a nightclub doorman by the 14K triads. But those mad parties ... you wouldn't have wanted to be anywhere else.'

John Parks, sound engineer: 'I fell asleep once on a sofa. The bouncers objected to me sleeping and I objected to being moved. They ripped me loose and I couldn't move my arms for a week.'

Burridge: 'The lights coming on and Spencer [a regular] being blue [he lived]. The drive to Christian's house most nights to carry on. Leaving my records in a taxi then finding them in a second-hand shop a week later.'

Trotter: 'Later on, the pills seemed to get worse as the triad element moved in and made copies with ketamine.'

Marco: 'Richard, a Frenchman, 28, was a mate who lived literally above Neptunes. He did drugs, started going down heavy on smack and shabu in 1996. He had a crush on a triad girl. In February 1997, apparently alone, he climbed to the top floor of an adjacent building in Lockhart Road and fell to his death.'

Change

Peter Upton, rave promoter: 'There was talk of tanks rolling over the border. One Nation at Bar City had more than 2,000 clubbers mash-up partying like the world might end, Canto-pop stars dancing with Hong Kong's finest. People walked in under British rule, and walked out wasted into China ... then down to Neptunes.'

Bennett: 'I spent the handover spangled in a sampan heading for Unity [the handover party at the Hong Kong International Trade and Exhibition Centre].'

Burridge: 'I always felt, as Hong Kong had a sell-by date, that people partied more often. Their behaviour was more hedonistic.'

Berentson: 'The fact that Hong Kong was being handed over to the Chinese as well as the fact that we really didn't know what to expect post 97 certainly added to the fervent nature of the average party-goer.'

Requiem

Corbett: 'I left a year after the handover. By then, I only knew about five people. But over the years I have caught up with many of [the Neptune crowd] in clubs, on dance floors, all over the world.'

Berentson: 'It amazes me hearing the word 'Neptune' said with great gusto and respect by the thirtysomething business types who were in their late teens and the older international DJs who still frequent our shores.'

Anderson: 'They were both the best years and potentially the most dangerous years of my life. Having come out relatively unscathed, I wouldn't trade them for anything.'

Kay: 'In Hong Kong at that time there was so much opportunity - all my friends were journalists, architects with zero experience but enough balls to get out there and give it a go.'

Fitzgerald: 'Acquaintances became friends down there, or friendships were cemented. I have friends all over the world and the one thing we have in common is stumbling out of Neptunes into the sunlight.'

Burridge: 'I've personally never experienced any 'lows' by being part of the Ecstasy generation. My mind was forever opened to a different way of socially interacting and connecting with the feeling of music.'

Thrall: 'When I wrote Eating Smoke, in 2010, I genuinely never expected to get back in touch with anyone from Hong Kong. Now that Facebook has united us, many of those colourful characters that you could only meet in Hong Kong are back in my life.'

Upton: 'We were all living to the backdrop of a soundtrack back then. For me it was a career, too, and I believed it would take me on to success. It's become a distant memory.'

Marco: 'The Hong Kong summer of love period is one big happy memory. I've never felt as cool, or as young since then.'

Trotter: 'Now we are all a bit older, some with families and parental responsibilities, it would be selfish and dangerous to carry on to the degree we did then.'

Some of the names in this article have been changed.

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