Yves Klein, at his very bluest

As a painting that scandalised Paris comes up for sale, Arifa Akbar speaks to the gallerist who made it happen

It was a musical performance with a twist that sent tremors across the art world when it was staged in 1960. An artist wearing white gloves and a tuxedo emerged from behind a screen to conduct an orchestra in front of a tastefully dressed Parisian audience at the Rive Droite art gallery. As he did so, numerous naked women sashayed out carrying pots of blue paint. The paint – a shade that would later be immortalised as an Yves Klein blue – was smeared by the models on to their naked breasts, pubic area and the length of their torsos.

Some of these women got down on the floor and began writhing their bodies in puddles of blue paint before, as "living paint-brushes", pressing themselves against a blank canvas to create a series of artworks.

This performance, resembling an avant-garde mud-wrestling session and culminating in the dramatic strains of the orchestra's "Monotone Symphony" (a single 20-minute sustained chord followed by a 20-minute silence) was meticulously orchestrated by Yves Klein, the French artist who scandalised bourgeois society with his bright idea and who has since come to be known as the god-father of conceptual art.

The paintings that emerged from this performance – and another one like it – have since become some of the most sought-after contemporary artworks of the age. Last month, one such canvas, "Ant 5", was sold by at auction for £4m, nearly £3m above its estimated price. And Christie's is to sell another, "Le Buffle", in New York in May. It is estimated to fetch $10m.

The wider art world outside Paris's Left Bank bohemia may never have seen this performance had Klein not enlisted the Swiss gallerist, Georges Marci, to film everything. Ms Marci, now in her 70s, told The Independent how it all happened.

A year befor the show, she was in her early twenties and running the Rive Droite Gallery in Paris when Klein, came in, said he had fallen out with his gallery, the Iris Clert, which was opposite, and now wanted to be represented by Ms Marci. By the time the show was staged – and tightly controlled by the flamboyant painter – they had become firm friends.

"The scene was really thrilling because he directed the girls who were models to move in certain directions on the paper which was spread out on the floor," she said. "They applied the paint themselves, but the rhythm with which they moved was dictated by Yves Klein. The women were completely directed and under the spell of the eye, movement and words of Yves Klein. Before the performance there was a rehearsal with the same models but no paint and no music. Yves Klein indicated their precise choreography so there could be no mistake."

After the event, Klein said: "I personally would never attempt to smear paint over my own body and become a living brush; on the contrary, I would rather put on my tuxedo and wear white gloves. I would not even think of dirtying my hands with paint. Detached and distant, the work of art must complete itself before my eyes and under my command."

Klein and Ms Marci had placed adverts in various French newspapers asking for women to come forward for theproject. Response came from many professional models who were "very young, and enthusiastic about working as human paintbrushes", said Ms Marci. (Some of the naked models are still alive. One, the inspiration for "Ant 4", is in her seventies, and said to be a yoga instructor in Holland.)

Klein's more prudish contemporaries condemned his show as salacious, but Klein's experience living in Japan, witnessing the human tragedy in the aftermath of the Second World War, had led him to incorporate the human body in his artwork. During the 1950s, in Hiroshima, he was overcome at the sight of the imprint of a body on a wall, left by the first of the two atomic explosions that would end the war.

"He felt that a person can die physically but his spirit can live on indefinitely and cannot be erased," Ms Marci said. "Klein was a very spiritual person and was deeply moved. This is possibly the birth of the idea of the human paintbrush."

In spite of the electrifying atmosphere, Ms Marci said she was not tempted to become one of Klein's subjects. "Given the circumstances of being his worldwide representative, it would not have been appropriate for me to be a living paintbrush. It was completely energy- and time-consuming just trying to cope and digest the tremendous creativity of his various projects and help him realise his ideas."

Francis Outred, the head of Christie's postwar and contemporary art in Europe, said: "His whole artistic premise shocked Paris. He's now seen as the godfather of conceptual art. We would not have had Andy Warhol, or Jeff Koons, or Damien Hirst, without him. He presented the poetry of the idea as the basis of his art. If you watch [the show], there's a glint in [Klein's]eye. He understood the wit in it as well as being a pioneer of a new way of making art."

Even today, Ms Marci's film has a healthy number of hits on YouTube. One comment reads: "A bunch of white men in suits watching nude women doing stuff. Art, at its finest."

Bodies of work: Artists and nudity

*Ron Mueck uses silicone and human hair to produce hyperrealist sculptures of the human body.

*Spencer Tunick has taken photographs of mass gatherings of nude people al over the world.

*Marcus Harvey's portrait of moors murderer Myra Hindley was created using children's hand prints.

*Anthony Gormley used his own body as a cast in several works.