ORANGE, red, purple, blue, green . . . orange, red, purple, blue, green. Ahh, the delights of one’s very own infinity chromatherapy bath.

Bubbles are burbling gently below. Water is trickling, almost serenely, over the porcelain bath edges, creating the “infinity” feel: as though I’m bathing in the sky, above the mundane concerns of the everyday world. Underwater lights are flickering through their colour sequence — the chromatherapy “light massage” working its strange magic. Miles Davis is filtering through from the state-of-the-art Bose stereo in the master bedroom.

Oh yes, one could certainly get used to this. But one had better not — for one can certainly not afford it.

This week I was the first guest at Britain’s most expensive hotel suite, in the Langham Hotel on Portland Place in Central London. It’s directly opposite Broadcasting House, overlooking the pretty steeple of All Souls Church.

It has two bedrooms (the master and a twin for the kids, guests, or whoever). It is 236 square metres. It has lots of giant flat-screen televisions (32in, like mini-cinemas). It has its own butlers (Oliver and Ricardo, very nice helpful guys). It has loads of interesting, specially-commissioned pieces of contemporary art. It has the IBM Thinkpad on which I’m writing this (with broadband, of course).

And it costs — £6,169 for one night.

That makes the Langham’s Infinity Suite the most expensive in the UK, ahead of the Lanesborough, on Hyde Park Corner, which is next on the high-spenders’ list at a measly £5,875. Forget The Savoy (£1,250), the Mandarin Oriental (£5,287) and Claridge’s (£4,548). This is now the place to stay in London for the mega rich. Or so the Langham hopes. Can a £6,000-plus room really be worth it? There was only one way to find out.

Our limo (the suite comes with a car and driver, available for three hours a day) picks us up at 6pm on the dot from Times House. Johnny, the driver, has arrived early and is holding open the office door for bemused Times hacks as they depart for the evening — it’s in his training.

We are whisked in Johnny’s Audi A8 six litre W12 Quattro — “there are only three of these in the country” — to the Langham. “The things I could tell you about celebrities who ‘have been in here,” he tempts us. “It’s the driver’s code not to say a word — but there’s a certain footballer’s wife . . .”

The hotel staff are waiting on the marble steps to the entrance. “Hello sir. Good evening. This is Ricardo, your host for the evening.”

Champagne, 1996 Laurent-Perrier, is on ice — also part of the price — with the delightful Nuria, the hotel’s head sommelier, there to serve us. Ricardo is busy preparing the table for our dinner, and Oliver is passing around a tray of canapés (smoked salmon, foie gras). We could get used to this.

We take a look around. “Oh this is lovely,” says Joanne, a Times Travel designer. “Beautiful — oh, I’m going to be bitter and twisted for life after this!” says Jo, who works on the picture desk. Both, along with Steve, who works for Times Online, have with great self-sacrifice (and speed) volunteered to assist in my research.

The decoration is modern: slick, high-tech, but not OTT — created by RPW Design, of Ritz-Carlton, Gleneagles and Swan Hellenic renown. Purple, chocolate brown, ivory, gold and red feature in the colour scheme, with cream carpets, a marble entrance hall, low-level lighting and a fantastic drawing room with a curved wall of windows.

I’d checked out the Lanesborough, the Mandarin Oriental and the Savoy suites earlier in the day, to make a comparison. They were all excellent, as I saw it, in the order listed, but their plushness was Victorian, full of antiques and oriental vases — in a word: traditional. The Langham’s luxury is 21st century, without being flashy.

Our meal (a mere £195 per person extra, wine included) is terrific: cappuccino of white haricot soup, lobster with buttered cabbage, wild sea bass and beluga caviar, cheeses and an excellent apple tart. Nuria has chosen wines to go with each dish, including an excellent riesling and burgundy — “top notch”, says Steve.

Joanne selects music to play on the stereo and Ricardo changes the CDs. He also disappears to fetch a film for her camera when she asks. We retire to Tsar’s, the downstairs vodka bar, for cigars and a final tipple. It is dark and shadowy, with flickering candlelight. Perfect.

The Langham was, until last May, a Hilton franchise. But its parent company, based in Hong Kong, has decided to take on the management itself and spruce up its stock, with the Langham in London as the flagship leading the way.

The Infinity Suite is the first room to be revamped, at a cost of £700,000. The rest of the rooms and the public areas will be next. We can’t help noticing, as we walk about, that other parts of the hotel, including Tsar’s, do not live up to the suite’s high standards.

Downsides of the suite itself are hard to find — which you would expect at more than £6,000. Joanne thinks the view could be better — “I don’t like that office block” — and it is true that the Lanesborough’s (across Constitution Hill) and Mandarin Oriental’s (across Hyde Park) are superior. Jo doesn’t like one of the pieces of art: a star-gazing polar bear sculpture. And I’m a bit disappointed that one of the surround-shower sprinklers doesn’t work.

But all this is nit-picking. I had a great time, a good infinity soak and a sound night’s sleep. Jo’s verdict was: “I feel as if I’m in Pretty Woman!”, Joanne’s “Cor, lobster ravioli!”, and Steve’s: “I really like it.”

So if you’ve got six grand to spare and want some fun, then go for it.

Details: 020-7636 1000, www.langhamhotels.com

IF THE PRICE IS RIGHT

The Langham’s Infinity Suite may be expensive — but it’s far from being the most expensive suite in the world.

That title, as far as we know, is held by the Imperial Suite at the President Wilson Hotel (00 41 229 066666, www.hotelpwilson.com) in Geneva — £22,050 a night. Overlooking Lake Geneva, it has six bathrooms, a billiard table, cocktail lounge, Steinway grand piano, Persian carpets and a library full of antique books. And it’s a massive 1,200 sq m.

In New York, the Four Seasons Hotel New York (www.fourseasons.com) has two Presidential Suites designed by I. M. Pei, the renowned architect, for £9,137. The two-level Presidential Suite at The Plaza (020-7025 1625, www.fairmont.com) seems almost cheap at £2,460 with its six bedrooms and roof terrace on the 18th floor.

The top suite at the Burj al Arab (00 971 4 330 0111, www.jumeirahinternational.com) in Dubai costs £6,634, on the 25th floor complete with rotating bed, private lift and chauffeured Rolls-Royce.

In Paris, the Four Seasons Hotel George V (00800 6488 6488, www.fourseasons.com) has Royal Suites at £6,267 a night — four-poster bed, marble bathroom and sauna.

And in Bali, the Begawan Giri (00 62 361 978888, www.begawangiri.como.bz) has a Royal Suite that consists of four bedrooms, plus a private outdoor terrace pool from £2,844.

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