Reputations in the balance for riskiest stunt in the world

JIt is possibly an act of utter madness. In today's overwhelmingly safety conscious climate, two men are intending to walk across a tightrope suspended 150ft above the River Thames. Without a safety net. All being well, Didier Pasquette, a Frenchman, and Jade Kindar-Martin, an American, will cross each other in the middle, one continuing towards the Oxo tower on London's South Bank, one to Victoria Embankment.

If they are successful, the pair will win themselves a place in the Guinness Book of Records. If not they could plunge into the water at approximately 60mph to almost certain death.

Appropriately 1997 is the centenary of the death of the most famous wire- walker ever, Gravelet, better known as Blondin. In 1859 he walked across Niagara Falls but although he settled in London he never attempted to cross the river. In fact, the distinction of the first successful crossing belongs to a woman, Madame Genevieve. After two attempts she finally succeeded in 1861. A writer at the time described it taking place "in the light of the declining sun, her gold-broidered dress and white pole gleaming refulgently".

During this century a Frenchman, Charles Elleano, in 1951 and a German, Franz Burbach in 1972 have also pulled it off.

In the village of Trainel in the Champagne area near Paris Mr Pasquette and Mr Kindar-Martin are making their final preparations for the attempt a week on Sunday which will launch the annual Thames Festival. They have erected in a cornfield a similarly sized wire which they estimate will take 45 minutes for them to cross.

Within sight of a nuclear power station, poplar trees swaying in the breeze, they contemplate their potential place in history. "Getting a record isn't my interest," Mr Pasquette, 29, said. "Walking a tightrope is something really special - you can't know until you've done it." A former member of the Archeos circus he has been wire-walking since he was 17 and in 1991 walked a rope strung between the twin towers of Wembley Stadium, north-west London.

Both performers have identical scars on their shoulders where, in separate incidents, their tricks have backfired. Yet falling off the wire is a prospect that neither of them give much consideration to. "You need to be vigilant and ready for the unexpected," Mr Pasquette said. "When I'm up there my goal is to get from one point to another. My wife is a little bit afraid but I don't want to think about falling."

Mr Kindar-Martin, 23, began learning circus skills at a summer camp in the United States when he was 14. Like Mr Pasquette he insists that nothing would ever deter him from pursuing his chosen occupation. "Either I die or I don't," he said airily. "I see this as my life. I know I wouldn't feel complete if I stopped. There are so many people in the world who flow through their lives. They don't pay attention and they're not really there. But we're not just existing, we're actually living. Every step, every breath, we're conscious of it."

Strangely both walkers fiercely deny that they are danger junkies. "We're not addicted to the rush," Mr Kindar-Martin said. "I don't even drive fast."

However, he added that balance is a "magical thing". "Sometimes you have it, sometimes you don't," he shrugged.

The police are already predicting that 60,000 people will turn out to watch this spectacle.