The stars arriving to be filmed at a small London production house were "stacked up like aeroplanes coming into land", recalls Simon Dicketts, executive creative director of advertising agency M&C Saatchi.
Acting talent of the calibre of Alison Steadman, big names such as Jerry Hall, Cherie Blair, Joan Bakewell and Geri Halliwell. All of them queuing up to make a television advert and none of them getting paid.
But more exciting for Dicketts than working with any of these celebrities was the presence of the man standing behind the camera, the Bafta award-winning film director Mike Leigh.
When Dicketts embarked on putting together an ad campaign for the charity Breast Cancer Care, he had only one individual in mind to direct the commercial. "I chose him because he's simply the best person I could think of to do it - we needed it to be very honest," he says.
"I saw Vera Drake the other day. It's so haunting. He allows actors to be very naturalistic and gets them in the right mood and lets them get on with it. You see some very raw emotions."
It is no mean feat to persuade the director of such authentic and uncompromising work as High Hopes, Life Is Sweet and Secrets & Lies to dip his foot into ad land and make a commercial. But, says Dicketts, the deal was done in 15 minutes with a handshake and no question of a fee.
"He has delivered exactly what I wanted," says Dicketts of a commercial that features 10 famous women - each with some experience of the damage caused by breast cancer - speaking a line in turn about the work of Breast Cancer Care.
The sentiment of the powerful piece, written by Dicketts, is that "if breast cancer could choose" then the insidious condition would rather that such a helpful and powerful human resource as this charity did not exist.
The day-long shoot at a studio near London's Regent's Park saw the celebrities (also including Denise Lewis, Denise Van Outen, Zoë Ball, Lorraine Kelly and Meera Syal) flocking to work with Leigh.
"He has a formidable reputation and it was incredibly helpful to have him doing it because the people we approached wanted to work with him," says Dicketts.
Each of the women was filmed reading the entire script and the commercial was edited together with the celebrities performing one line apiece, to give the effect that each was reinforcing the words of the others. Dicketts says that such editing gave the commercial (which is running until 6 April and is allied to newspaper ads) the "right intensity and cadence". He says: "You should feel afterwards that everyone who appears means every word of it - it's like a manifesto."
Working with Mike Leigh, he says, was a two-way process. "It's a very short line of communication. He's very receptive and understands what you are talking about. For someone so talented, he's unusually respectful to people around him. Sometimes people can be a bit prima donna-ish."
Leigh suggested only one change to the script, a piece of repetition that gave emphasis. Dicketts says: "He said, 'It's your thing and I'm anxious it comes out how you want it.'"
Will Leigh be prepared to do any more commercial work? The experience does not seem to have set him against it. He issued a written statement saying he was "delighted" to have had the opportunity to take part.
"I have always admired Simon Dickett's work," he wrote, "and thought this was the perfect opportunity to work alongside him as it's for a worthy cause. I hope this campaign raises awareness of Breast Cancer Care's services."
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