I am in a toilet cubicle, in Boujis. I came in here for fairly conventional reasons, but I have found myself curiously unwilling to leave, even though the whole place vibrates with every B of the R&B playing outside. On reflection, I think it’s because I’m sitting down. I haven’t sat down in hours. I’m beginning to understand why Prince Harry always seems to be staggering when he is photographed coming out of here. It’s because he’s knackered. It’s because there is nowhere to sit.

My mission was simple. I was to come to Boujis, this curious, dark, sweaty, expensive, tiny club on a busy roundabout in West London, and next week I am to go to Mahiki, its greatest rival, opposite the Ritz. I was to figure out what it is about them that makes them so popular with the kind of people that paparazzi snap for tabloids. Probably it is not the toilets. Probably that’s just me.

So, Boujis. First things first: getting in. Not so easy. I have recruited Jemma Foster, a fellow journalist, who is plainly a Boujis regular, but denies it. She knows somebody who knows somebody, and reckons we won’t have a problem.

“Meet me at 10.30pm,” she says, which surprises me, as it is a Tuesday.

Weird night to go out, Tuesday. Or rather, weird for you and me. That is because we have jobs. Jobs, I learn, are disapproved of at Boujis. Plenty of people probably have them, but they pretend they don’t. That’s why Tuesday is the biggest night. If you can go out at 10.30pm on a Tuesday, the thinking must be, you are also the sort of person who doesn’t need to work.

Despite being with Jemma, who definitely comes here quite a lot, and despite her knowing the person she knows, who, if I am remembering this rightly, knows somebody else, we queue for about an hour. It’s not so bad, provided you aren’t bothered by paparazzi, and provided you smoke. You see, the smoking area is right next to the queue, also outside, but fenced off with a little red rope. They smoke, you smoke. You can even look down on them a bit, because they’ve paid an enormous entry fee, and abandoned their warm coats, just so they can go downstairs and come upstairs again, and stand back exactly where they were before, smoking. They’ll probably look down on you, too. People do. This is Boujis.

We get in, eventually, and pay the enormous entry fee (£15, or thereabouts), and then we are inside. It’s dark in here, and it is packed. Also, my clothes are all wrong. I’m wearing a linen suit and a t-shirt, because these are the most expensive clothes I own. A mistake. As a nice Boujis man, I ought to be wearing brown brogues, a pink shirt and dark blue jeans. Unless, that is, I’m going for the nasty Boujis man look, which is the same, but with black brogues, a blue shirt and an expensive leather jacket. Nobody looks like me. I feel like Martin Bell, in a war.

Women all wear minidresses with flared sleeves and small heels if they look under 35, and black jeans with dark vests and bigger heels if they look over 35. All of them. Literally, all of them. Everybody is individually stylish in an utterly homogenous way. The ceilings are low and the place is hardly lit, but still. Everybody looks the same.

I’m not sure what you drink, at Boujis. I’m not even sure what I drink. There are men at the bar handing over bundles of twenties and getting champagne in ice-buckets. I’m not really up for that. Jemma speaks to the bartender and gets two shots and two cocktails, and the bartender gets, I think, £87 from my Switch card. Then we try to sit down. We can’t, of course. To sit down you have to have booked a table, and to book a table you have to have convinced management that you are going to spend enough money to deserve a table, which is to say about £800. The music is all utterly Radio 1.

So we stand, as women over 35 stand on my foot, and women under 35 shove their flared elbows into my belly. Possibly, they are trying to feel how thick my wallet is. There is an awful lot of snogging going on. Plus, everybody here seems to know each other, whether they are snogging or not. Boujis, I realise, is a provincial meat market. It just happens to be in the province that is the most expensive part of West London. It is like a grown-up version of the under16s discos you get in Cornwall golf clubs. Fumbles on the dance floor and Marlboro lights in the car park.

While smoking, I watch a woman in a ludicrous pink party frock and a tiny top hat getting turned away by incredulous bouncers. I’m not surprised. Tomorrow, I’ll see her picture in The Sun, and realise she is Charley Uchea, a Big Brother contestant. Why did she even want to come here? It’s like gatecrashing somebody else’s school disco.

Eventually, you do really need to sit down. So, off to the toilet it is. As I rest, safe in my cubicle, I can hear two men arguing by the sinks, in what sound like Middle Eastern accents.

“I need another hundred more,” says one.

“I’ve got 500,” says the other. “That’ll do,” says the first. The following morning, Jemma texts me. Apparently Kate Middleton was in Mahiki.

And thus, a week later, so are we. Or rather, we are outside Mahiki, in a side road opposite the Ritz. Again, Jemma knew somebody who knew somebody else, but this time the somebody else doesn’t appear to have known whoever it was they pretended to.

Mahiki claims not to have a guest list, but some people get in and some people don’t. That night, we don’t.

“I’m getting no love!” shouts the guy behind me in the queue. “Let’s start our own club, and not let them in!” “Nah,” says his friend. “Let’s go to the Ritz.” I, too, am getting no love. Blue Peter’s Konnie Huq turns up, and she gets in, and the paparazzi are all convinced that Naomi Campbell is in there, too. Then Luke Blackall, the gossip columnist from thelondonpaper arrives, and after a brief chat with the bouncer, he’s in, too. For the gossip columnist on The Times, that’s frankly humiliating. We leave.

The following week I cheat, and call up Nick House, the London club promoter who, along with Piers Adam, the owner, set up Mahiki in 2006. So instead of standing outside in the cold, I get inside, with the boss. Hardly an objective experience, I know.

Still, no toilets for me. Mahiki is weird. The furniture is all bamboo and my first drink is a “Pieces of Eight” which I share along with a couple of other people at my table (yes, I have a table). It’s a large children’s toy treasure chest, filled with . . . hmm, punch of some sort. I think it costs about £100, and obviously you are meant to share it. Ideally with people who don’t gross you out when they slurp at the end of your straw with their own. They also serve drinks in pineapples, barrels, coconuts, hollow statues and divers’ helmets.

“It’s bonkers in here,” I tell Nick House, above the booming noise of, I think, Wham!

“It’s meant to be,” he says, thrilled. “That’s why it works. It breaks every rule of clubs! It’s not cool! There’s no guest list! There’s no VIP room! You get drinks that come in helmets. It’s just wrong. Not everybody gets it. Do you get it?” House, as I almost certainly should have already mentioned, is dressed in a long black cape and a Venetian opera mask with an insanely long nose. Tonight is a fancy dress party, which sees Mahiki, I should think, at its most Mahiki. Fancy dress nights happen at least once a week.

I think I do get it. Most reviews describe Mahiki as “cheesy”, which isn’t quite right. There’s a bunch of tables upstairs and a ludicrous dance floor downstairs and actually, cheesy is what it looks like if you don’t quite grasp what is going on. In truth, it does everything it can to break down traditional nightclub pretensions. Customers should feel that their life in here is utterly separate from their life outside, because nowhere else would they be handed a drink in a pineapple by a man with a plastic parrot on his shoulder. You’ll get a group of posh Chelsea students at one table, a 60-year-old Arab man with a 17-year-old Russian hooker at the next, and a group of very lucky Essex girls at the one after that. Chances are, they’ll all be talking. Fundamentally, this is a nightclub for people who don’t like nightclubs. Here with a group of friends, I’ve a feeling I might actually enjoy myself.

Although, if I hadn’t written this article, I probably wouldn’t get in. And let’s be honest. You, gentle reader, probably won’t get in. And even if you do, and you see me there, we’ll both be struggling to afford to get drunk. As I leave, pretty early, a werewolf is carrying a bunny girl down the stairs.

The next morning, Nick House sends me a text. Apparently I just missed Kate Middleton.

The Tuesday night look

Boujis man is surgically attached to his pink shirt from Jack Wills – an English Ralph Lauren who provides ski, weekend and party gear for the well-heeled SW3 male. A bargain at £69, the shirts must display the italic JW on the pocket. Jeans are understated but knowingly expensive, from Armani, 7 For All Mankind or Harvey Nichols. Shoes must be brown, with the box-fresh, Eurotrash look of an off-duty footballer, mostly from Tods. Gucci is another contender, but gold buckles are a nono. Liberal amounts of gel in the hair achieve a perfectly slick crowning glory.

Boujis girl shows off her curves in empire-line dresses from Jigsaw and Paul and Joe – the shorter the better. Those wishing to show off cleavage instead of leg find sparkly vest tops on the fourth floor at Harvey Nichols: Splendid, Ella Moss and D&G provide the deep-plunge look. Shoes must be strappy and have a heel: favourite haunts are Jimmy Choo, Gina and Christian Louboutin, probably in the sale. Jewellery is either sparkly or ethnic: the former from Topshop, the latter bought on their extensive travels. (Alice Olins)

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