It was a relief to get out of the fierce midday sun in Soho, Central London and go through the cool reception of the Courthouse Hotel - Kempinski downstairs to the Sanook Spa. Although I was pleased to have sought out some subterrannean shade the therapists, who’d been cooped up in this small underground spa, craved sunlight.

Despite its mini size the spa has a boxy swimming pool with waist-high water. It is overhung in one corner by a glass cabin where after a quick dip and a challenging shower - the single shower had so many controls that it spat things out at me from unlikely angles - a light spa lunch was served. This comprised a tasty stack of sea bream with tarragon, fine green beans and freshly squeezed orange juice - suitable spa fare and delicious. It was accompanied by Voss artesian water from Norway in shampoo-style bottles. Perched alone above the pool, I felt like a Bond villain and expected any moment to see shark fins through the reinforced glass floor.

In the big scheme of things it’s the people and treatment that count but the reputation of a luxury hotel is forged in details – the used plasters around the slate-crumbling edge of the pool, the dirty mats at the changing room entrances, and no bathing robe were minor flaws. The poolside fruit platter was a nice touch but had been well pecked at by the time I arrived. It was suitably replenished (like my bath robe) and it subsequently proved a true test trying to eat blackberries without sullying the Persil white robe.

Professional moans over, my therapist Bhavna was as chirpy as the exotic birds on the treatment room stereo – the same soundtrack sounded like a blocked cistern at one point during the 90-minute session, fortunately I’d de-Vossed beforehand.

Bhavna was entrepreneurial in spirit. Before we'd so much as opened a Karin Herzog unguent I'd been invited kindly to the Kempinski's sister spa, Le Kalon at the Bentley Hotel in Kensington and to her father’s vegetarian restaurant in Brent Cross. I wasn't, however, peddled any products.

She started my O2 Relax treatment (£85 for 120 mins) with a chocolate facial taster. "The cocoa bean has many health benefits including anti-ageing properties derived from its high antioxidant levels," said Bhavna. I tried hard not to lick around my lips.

I then had an all-over Ayurvedic-style exfoliant rub- firm but not too firm - before being painted with an anti-bacterial oxygen cream. This, according to the label on the side of the "tin", "uniquely increases o2 pressure to guarantee that the skin has the necessary energy to fully utilise vitamins for enhanced sustainable results." My sun-ravaged skin certainly felt supple and moisturised.

It was my feet, though, that got the best attention. It was strangely becalming to know that I was laid out beneath the frenetic sweating crowds of Oxford Street receiving a bonus tickle-free pedicure.

By the time Bhavna left the room my feet gleamed. They had been buffed and clipped to a state previously unknown. It seemed a shame to put them back into whiffy sandals – and foolish to go home in fluffy white spa slippers - so as soon as I was back on street level I picked up a new pair of flip flops and dispensed with the old footwear.

In brief

USP Its central Soho location and down-to-earth feel.

AMBIENCE The word sanook means "enjoy yourself" in Thai and there's a Buddhist tone to the decor at this slightly claustrophobic spa.

EXPERIENCE Relaxed but thorough. My feet had never felt so good.

FOOD The Silk restaurant is housed in the old courtroom no.1 and serves fusion food from the old silk route specialising in aphrodisiacs. You can also have a drink in former prison cells – which have been renovated into designer drinking cubicles complete with non-functioning lavatory. They would make ideal treatment rooms.

IN CROWD Me. At least I was the only one there on a midweek afternoon. Ordinarily the hotel houses an eclectic bunch of celebs, including David Hasselhoff, Jack Johnson, the Sugarbabes and Bollywood casts – who hopefully don’t all want to use the bedroom-sized gym at the same time.

WALLET WATCH An O2 Relax treatment costs £85 for 120 mins; 30-minute lunch-hour facials start from £35 and a 90-minute aromatherapy massage designed to help you sleep is £100.

NEED TO KNOW Sanook Spa at the Courthouse Hotel – Kempinski, 19-21 Great Malborough Street, Soho, London (0207 297 5555; www.courthouse-hotel.com)

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