50 Berners Street, London W1 (020-7300 1414; www.sandersonlondon.com)

Atmosphere and decor: The lobby of the Sanderson Hotel has space-age lifts and a pair of bold red lip-shaped sofas. By contrast, the Agua Spa’s all-white theme, from decor to furniture, creates a feeling of ethereal calm. There are decadent chaises longues on which to lounge and the changing rooms are luxurious, with demure dressing tables. Ceiling-to-floor muslin curtains act as dividing walls.

Treatments: Our spy indulged in the Enrich Treatment, which employs Aromatherapy Associates products, and a Rose Renew Facial. The former consisted of a vigorous scrub-down, followed by an invigorating shower that uses eight jets to target key areas of the body – unfortunately, for those of us below 5ft 7in in height, that means enduring a mouthful of water. The facial, which uses rose and sandalwood oils, famed for their protective qualities, is ideal for sensitive or mature skins – ultra-nourishing, it left our spy’s complexion glowing.

Clientele: As befits the achingly trendy Sanderson, hip meets yummy mummy.

Highs: The atmosphere of utter luxury.

Lows: The muslin curtains aren’t very effective at eliminating the noise from the reception area or nearby treatment rooms.

Marks out of 5: Four.

If you have a salon that you either love or hate, e-mail sarah.vine@thetimes.co.uk

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