The couple believes the world fur trade is barbaric

The couple talk passionately and candidly about their battle against the market for fur - especially a disturbing trade in domestic cat and dog fur.

The film follows Heather's recent campaign in the United States where she attends a star-studded Peta gala (People for the Ethical Treatment of Animals).

She also takes her protest outside, and inside, fur-friendly fashion stores, which includes a lively confrontation with security at Jennifer Lopez's own Sweetface label in New York.

REAL STORY: McCARTNEYS v FUR BBC ONE, Wednesday 19 April, 2006 2100 BST

Of fur-wearing "A" list celebrities, Heather says: "If I ever bumped into Cindy Crawford, Linda Evangelista or Jennifer Lopez, you know, there is no way I would be gentle with them because they've been informed time and time again."

Paul admits that, although now anti-fur, he once wore it in his Beatles days.

"Like most people we didn't realise when you wore a fur jacket, as John did on the concert tour on the roof of Apple, or as I did in the film Help... you didn't realise what you were doing by wearing fur."

High street fur

Viewers have a rare insight into the McCartneys' campaign strategy as Heather sets off for Brussels to appeal for an EU ban on cat and dog fur.

The couple reveal how Paul's influence reaches to the top of the political tree - as far as EU Trade Commissioner Peter Mandelson and Prime Minister Tony Blair.

The programme also looks behind the attraction of fur - now annually a �7bn global business. Talking to highly successful fur traders, their rich clients and a top stylist to the stars, it becomes clear that there are many who are yet to be convinced to ditch fur.

As Heather campaigns on the streets of Britain, the programme reveals how, with no legal requirement to label fur garments, high street shoppers in the UK could be unwittingly buying real fur.

The programme includes footage from fur farms in China provided by the charity Care for the Wild International.