Stephanie Irvine, the BBC's reporter in Morocco, headed down to Marrakech to try to gatecrash the extravaganza.

Spying on celebrities is not my usual kind of assignment. But last weekend that was my mission.

The rap artist Sean "P Diddy" Combs, formerly known as Puff Daddy Mr Jennifer Lopez, was coming to a town near me to celebrate his birthday.

The weekend promised to be a wild affair, but it was to be strictly private - no press allowed, except one approved photo agency.

The most scandalous thing that happened was a woman going for a swim in her underwear - and that was me

So when I caught the train for the magical southern city of Marrakech, I was just hoping to pick up some titbits - who was in town and what would they be doing?

Maybe a guide would tell me some anecdote of Nicole Kidman haggling in the market over the price of a pair of slippers.

The winding alleyways of the souq, or market area, was the first stop in my celebrity hunt.

"Come in and look, for the pleasure of the eyes," crooned carpet weavers and kaftan sellers, but I was on the lookout for stars not bargains.

All-night revelry

But my search was fruitless. It turned out the guests had been up partying until eight in the morning and were still in bed.

P Diddy had been dancing on the table at a posh restaurant, shaking his thing with the belly dancers, then they had descended on a local nightclub.

Marrakech: Ancient setting for the party

The five-star Palmeraie Golf Palace on the outskirts of the city was where most of the guests were staying.

There I met Norma, P Diddy's personal assistant, who took my press card.

Maybe I would be allowed to attend Sunday night's party, for an hour - if I was lucky. She'd let me know.

But, meanwhile, Saturday afternoon's pool party at P Diddy's rented villa, and the evening's do at the home of French Moroccan actor Jamal Debouze, were strictly private affairs.

No question of the press being invited, I was assured.

So with a sighting of French film star Gerard Depardieu under my belt, at three o'clock I was waiting at the hotel for the shuttle-bus to take me back into town.

That was also the time when P Diddy's pool party was due to start and guests were gathering in the lobby waiting for transport.

"Excuse me, are you going straight to the party?" one of the hotel staff asked me, mistaking me for a guest. "There's a van over there - hurry, it's about to leave."

Lucky break

So, after a moment's hesitation and trying to suppress a smile, I found myself sitting behind a group of young black Americans as we were chauffeured round to P Diddy's villa.

A pink Moorish castle with marble floors and a rose-petal filled fountain opened out to a garden with palm trees and a huge turquoise pool, around which were draped long-legged women in sarongs.

The people I arrived with gave high-fives to some large men wearing chunky gold jewellery, and I tried to look inconspicuous.

But if anyone wondered who the frump was in the beige linen trousers and the rucksack, no-one asked.

I spent the afternoon lazing on the grass, listening to Arabic rap fusion, drinking champagne and trying to recognise people among the host of musicians, models, dancers, fashion designers and film stars.

It was all very laid-back. The most scandalous thing that happened was a woman going for a swim in her underwear - and that was me.

Now that I knew how the system worked, it was easy to gatecrash the evening's party at the home of Jamel Debouze. I just had to get to the hotel, wearing my best frock, and hitch a lift with the real guests.

Fairy-tale setting

Camels and Berber musicians greeted us at the entrance to another fairytale villa.

The trouble with gatecrashing a party is that you don't know anyone there, and you are constantly afraid of being chucked out

I quickly lost myself among the beautiful people milling around the candle-lit gardens. Model Naomi Campbell was propping up the bar in a stunning white designer dress.

Tattooed rock star Tommy Lee, the ex husband of Pamela Anderson, watched some young women having their bellies and feet decorated with henna.

French rap dancers did an impromptu performance as a DJ played dance music and coloured lasers lit up the palm trees.

A winding staircase, whose way was blocked by security men, led to a VIP terrace.

From below I could glimpse in the light of the lanterns the shadowy figures of P Diddy and his close friends having their own discreet private party.

Actually I was dead bored. The trouble with gate-crashing a party is that you don't know anyone there, and you are constantly afraid of being spotted and chucked out.

So, after doing a live interview from the party over my mobile phone for the BBC at half past one in the morning, I bowed out and took a taxi back to my - very cheap - hotel.