Sch... you missed Camilla's wedding

They are the paparazzi pictures you thought you'd never see. The sort of intrusive images designed to send press watchdogs through the roof. In one, the camera peeks round a curtain into a grand room where a tiara-wearing Camilla Parker Bowles is apparently getting dressed for her wedding. She nervously sips a drink while a grey-haired man fiddles with her corsage. We even get to see her sensible bra in the mirror. From his glasses and the trademark black fan held coyly over his face, the dressmaker can only be fashion legend Karl Lagerfeld.

Another image taken over the shoulder of a prison officer shows a contrite Jeffrey Archer in his prison cell being comforted by Margaret Thatcher, who is clasping his hand in sympathy.

Certainly they are striking pictures, but glance a second time and something is not quite right.

If there are any remaining doubts in your mind, the logo at the bottom of the pictures should make it clear that these delicious shots are fakes and the people in them are lookalikes.

They are, in fact, advertisements for soft drinks brand Schweppes and carry the company's 35-year-old tag line: "Schweppes ... you know who" and a tiny disclaimer saying: "It's not really him/her."

Neither Archer's office nor Buckingham Palace would comment.

Three further images are expected to appear in the run-up to Christmas. All five were taken by controversial art photographer Alison Jackson, who specialises in recreating topical scenes.

Her best-known works include a photo last year of "David Beckham" wearing only a pair of his wife's frillies and a picture of "President Clinton" savouring a cigar while cavorting on the floor with "Monica Lewinsky".

"They aren't a joke, they are a serious comment on the nature of authenticity and the current obsession with celebrity and fame. You think they tell the truth but they don't," says Jackson.

Despite the best efforts of the Press Complaints Commission, the growing use of celebrity lookalikes highlights the lack of control that stars have over their own image.

In Europe and the United States there are laws restricting the commercial use of celebrity images without permission. Even dead celebs can sue in America.

And in this country, television watchdogs are very clear about the use of lookalikes. "You just cannot use look-alikes of living people on television without prior say-so," says media lawyer Robert Wegenek, partner at solicitors Hammond Suddards Edge.

The only way celebrities can protect themselves is to invoke the 19th century law of "passing off" which was originally used to protect branded products from imitators.

"The trouble is that it only exists to protect people's commercial reputation. But you do need a reputation to protect," says Wegenek.

"Camilla Parker Bowles would have to prove that she is a commercial property. And Jeffrey Archer currently has little reputation to protect."