As all sensible writers probably should in these credit-crunchy times, I’ve recently taken on a second career in pornography. I wrote my first story the other day, under a top-secret porno name, and was paid more money per milligram of effort than for any work I’ve ever done.

There was the small hurdle of nice-English-girl embarrassment to be overcome - but, once that had been swept aside (and what else is alcohol for?), it was difficult to stop. The joy of writing porn, apart from the money and the fact that you don’t need to worry whether the sentences scan, is the licence it gives to wallow in pure, unadulterated fantasy.

The story I wrote was set in the sort of fantasy apartment I thought existed only on the big screen. The sort of place (London? Miami? Paris? Who cares?) where handsome men in sunglasses exchange monotonal insults across coffee tables covered in cocaine, then shoot each other, often smashing plate-glass walls in the process, sometimes falling through them to their deaths.

Nothing like that happens in my porn story, of course, but the fantasy setting is right there. For those who enjoy their sex and/or violence served up with a bit of contemporary glamour, what more could one want? For those few who prefer it in less obvious (and so more sophisticated) environs, neither my smutty story nor this magnificent five-bedroom shag pad at No 1 Parliament View, in central London, for sale for £5.75m, is likely to be for you. Everybody else should look sharp and get saving.

This place is so absurdly, comic-strip glamorous, it put even my wildest fantasies to shame. There is a rather hefty £14,000 annual service charge, but if you can stump up the money to buy the place, this is mere small change.

All I could do when I first walked in was to stand in the middle of the 40ft open-plan reception room and giggle. The agent who was showing me round seemed to understand. He said he’d rarely, if ever, seen a pad - or penthouse, as he preferred to call it - that was quite so magnificent.

“It’s got one of the best views in London,” he said. I know we should take whatever estate agents say with a pinch of salt, but it is on the eighth floor and on the edge of the block. There are floor-to-ceiling, wall-to-wall windows on two sides, looking directly over the Thames, the Houses of Parliament, St Paul’s Cathedral, Westminster Bridge, Lam-beth Palace and the London Eye. It would have been silly not to believe him.

“Look at this,” he called while I was still goggling outwards. He was far away in the dining area, pointing a remote control towards a high bank of gently glowing cupboards. “You can make them glow pretty much any colour you like. And look at this,” he added, pressing another lot of buttons. A gentle hum followed and the vast, cream-coloured curtains slowly began to draw.

He wouldn’t reveal who the owner was, which was irritating. He said she was famous and keen on privacy - so much so that she had the windows specially treated to prevent people looking in. Luckily, most of her neighbours haven’t bothered with that nicety. And the block is crescent-shaped. I could have spent hours, weeks even, with a good pair of binoculars, gazing into their lives. I spotted a man in his underpants on the fifth floor, scratching himself and yawning. It was peculiarly fascinating.

There are few clues as to the owner’s character or identity, scour for them though I did. The place is artfully devoid of content, with only the odd piece of statement furniture to break up all the space. But there are mirrors everywhere: I imagine a modern-day version of Norma Desmond, the washed-up former silent-movie star from Sunset Boulevard, floating up here all alone, high above the rest of us, surrounded by nothing but her own reflection, forever preparing for that close-up.

A steel and glass spiral staircase leads from the main reception room to the master suite. There, before more floor-to-ceiling windows, a giant sheepskin rug adorns a blemish-free, bright-white fitted carpet. And in the middle of the room stands possibly the largest four-poster bed in the universe.

Moving slowly from the bed across that white-carpeted master suite landing, past the walk-in dressing room, we come to the the master bathroom. With steam room. Here, we might all like to pause, exhausted but satisfied, and imagine what it would be like to take a dip in that raised bathtub for two.

Or we might prefer to imagine - briefly, without an iota of bitterness showing - what it would be like to be the proud owner of a built-to-shag-in pad like this, then to find ourselves sleeping in that great big bed and sitting in that bath tub for two - all alone. Aargh!

Poor old Norma has had a steel lining installed in her front door to keep the world at bay, and the lift has a secret code to stop anyone accessing her floor.

Yes, yes, yes, reader: life in this gilded cage, gazing down on the busy lives of all those less fortunate ant people below, might sometimes be pretty lonely. Then again, we’re all lonely sometimes, ain’t we? Ho-hum. No comfort there.

Try again. The two characters in my story, finding their libidos flagging, decide to add a little lustre to their favourite pastime by doing it somewhere grubby. For ultimate satisfaction, they discover that an immaculate setting can be stultifying. Until our lottery numbers come up, it is a thought with which we should all console ourselves.

Not tempted? What £5.75m buys elsewhere

A fourbed, three-bathroom Georgian townhouse in Belgravia, No 34 Eaton Terrace is perfect for entertaining, with four reception rooms and a patio garden. The Grade II-listed property has consent to be extended. Savills; 020 7730 0822, www.savills.co.uk

Foscote, a Grade II-listed Jacobean manor near Buckingham, comes with all the country-house trimmings: three cottages, a pool, a tennis court, stables, 39 acres and seven bedrooms. Knight Frank; 020 7629 8171, www.knightfrank.co.uk

Es Cubells, on the party island of Ibiza, this modern white villa has four en-suite bedrooms, a large living/dining room, a staff apartment, an infinity swimming pool and spectacular sea views. Aylesford; 020 7351 2383, www.aylesford.com

1Parliament View, London £5.75m

What is it?A five-bed, 3,600 sq ft penthouse on a 990-year lease

Where is it? On the Albert Embankment, SE1

Who is selling it? Knight Frank; 020 7590 4653, www.knightfrank.co.uk

Times recommends

• Grand Designs Home of the Year entries think out of the modernist box
• Eco pioneer Wayne Hemingway shares his environmental tips
• Sir Stirling Moss on his Mayfair gadget house and Florida eco-home