Some investment bankers lead a varied life. If 35-year-old Emma Chan is not clinching deals at her desk, or snowboarding in Switzerland, she can be found chatting to celebrities on London's South Bank - in the nude.
Chan, from Twickenham, and her boyfriend Rob, who is also an investment banker, spent last Tuesday evening upstaging Nigella Lawson, Stephen Fry and Hugh Grant at the opening of the Saatchi Gallery in County Hall.
She was one of 160 'extra ordinary, ordinary' people who volunteered to take their clothes off in public for the American artist Spencer Tunick.
'It was so liberating. I just feel so lucky to be one of the few who did it,' she said. Chan and her fellow nudists were tempted into participation by the offer of a signed photograph of the event and they were not paid. The disparate group had been recruited through a listings magazine after art collector Charles Saatchi secretly commissioned Tunick to create a nude tableau to launch his contemporary art gallery.
'I automatically applied to join in,' said Chan. 'I had already taken part in his Greenwich installation with my sister, although I had never done anything else like it before that.'
Along with the other volunteers, Chan and her boyfriend were asked to take their clothes off and lie flat on the terrace of County Hall as the sun set. After their exposure, they were invited to the champagne party inside - on condition they keep their clothes off.
'At first when we heard we could go into the party as long as we went nude, we all said no,' recalled Chan. 'But then, after the photographs had been taken, our adrenalin was running so high that we just went in. We all thought "Well, we are art and these people are here to see art". The funny thing was, I didn't feel naked at all.'
Strolling past Jade Jagger and Tracey Emin, Chan found herself being photographed with Channel 4 news presenter Jon Snow.
'People talked to us about what was on the walls,' she said. 'But I looked around at one point and there were three women taking photographs of me.'
The fact that Chan had already taken part in another Tunick tableau makes her something of a veteran. The artist prefers to work with newcomers.
'I don't really use the same people,' he said. 'I try to stay away from nudist organisations. On Tuesday they were just everyday people and they often have strong reactions because it might be the first time they are nude in public. They each have their own reactions to participation. Most people think they can predict what it feels like, but it's a collective, new experience for the body.'
In New York, where Tunick lives, he customarily appeals for helpers by handing out flyers on the street. 'I never wanted to have the same people following me around, so I just hand them out. Occasionally someone finds out about it, but it is usually fresh people who take part.'
One of the newcomers last week was also the oldest participant. Sixty-one-year-old Jane Roberts from Winchester has never had any interest in public nudity, but took the train to London on Tuesday to disrobe on the South Bank.
'I didn't even know it was the opening of the Saatchi Gallery,' she said. 'But once we were all there there was such a good atmosphere. Spencer was very reassuring.'
Roberts also joined revellers at the party. 'I couldn't believe I was walking around naked with all these famous people. Lots of people congratulated us. I did it because I firmly believe the body is something of beauty and in a way this was a challenge to people. I thought, "I am old, fat and short - come on, accuse me!"'