A drama on the high seas - and in the courtroom

Amid a three-year dispute between proud rivals, the America's Cup begins on Monday with tensions spilling over

As an exercise in the bizarre, the America's Cup has always been right up there, and the parade of the weird and the crazy on Monday off Valencia, Spain, has the additional factor of being built on a foundation of bitter rivalry as potent and toxic as anything seen in its 159-year history.

Billionaires are lining up against each other like prizefighters, old friends are on opposite sides in a winner-takes-all struggle. You don't need to understand anything about the game to realise that here is the prospect of some very expensive blood on a very public carpet. The rivals are horribly exposed, egos are going to be bruised, the humble pie awaiting the loser has been cooking for over two years. The weapons of choice are boats, but no ordinary boats. They are unlike anything seen before, giant multihulls, not just fiendishly difficult to sail but downright dangerous. Make a mistake and they can catapult the crews into the water. Overload them and towering masts can come crashing down.

No wonder the crews will have crash helmets handy as hulls can fly between 20 and 40 feet in the air at speeds up to 40 miles an hour. They are very, very fast but both will want to go as slowly as possible while still winning. Nursing them round the course is as important as scrambling for a performance edge.

The holder of the sport's oldest trophy is Switzerland's Alinghi team and the challenger is the San Francisco-based BMW Oracle team. But the challenge very nearly didn't come. Even the most hardened of America's Cup enthusiasts have had their patience stretched beyond breaking point by a continuous barrage of complaint, accusation and insult. The billionaires are Ernesto Bertarelli, inheritor of a pharmaceuticals empire, and Larry Ellison, creator of the Oracle computer software house. The friends are Bertarelli's skipper, Brad Butterworth, a Kiwi who won three America's Cups and the man who was his skipper, Russell Coutts. Coutts, a fellow Kiwi, won and defended the cup, was wooed by Bertarelli and won it again before they fell out. Enter Ellison, who snapped up Coutts to put him in the opposite corner to Butterworth, who took over his old job at Alinhgi.

Bertarelli set about organising the next defence, originally scheduled for last year. But Ellison was ready to throw a spanner in the works. His lawyers complained that Bertarelli's Alinghi team had broken the rules and claimed the sole right to challenge the Swiss holders.

The New York court agreed with Ellison and forced Bertarelli, a long-experienced catamaran sailor on Lake Geneva, to set about building his defence weapon. He is threatening to steer it himself, Oracle is relying on an Australian whizz helmsman called James Spithill.

As the America's Cup is organised unlike any other event in sailing, or any other sport for that matter, that also cut out all other potential challengers, including Britain's, to contest a best of three. The result is something of a soapbox derby on super steroids, except that there are quite a few Nasa scientists who would like the sort of carefree budgets and blue-sky thinking that the best in yacht design and engineering have been allowed to indulge in a mere yacht race.

Both sides say the other has spent a ridiculous fortune and both say the truth, in their own case, is much more modest. Halve what they both say and it comes to $250m (£158m). Accept what they both say and that becomes half a billion. At that rate, if it is all over in two races and they last two and half hours each, that is $100m for an hour's racing.

That includes legal bills run up in the New York Supreme Court plus little incidentals like the renting of a helicopter for a month last year to ship the defender yacht from Switzerland over the Alps to Italy, and chartering a special ship to bring the challenger yacht from San Diego, through the Panama Canal and across the Atlantic to Spain. That's just petty cash.

Even though the contest should be done, weather willing, by next weekend, should Alinghi win Oracle will go to court claiming that part of the Swiss boat was illegally built in the US. The entire boat must be constructed in the team's homeland.

The bookmakers find the winner a tough one to call but should there be light breezes expect Alinghi to be favoured, in fresher breezes Oracle should be more powerful. It would do the sport the world of good were it to be tight and exciting and go to a third race decider.

This is a dish which has been a long time coming, but now it's here it has the perfect ingredients for a great event.

America's Cup: How it works

*This year's event is the 33rd staging of the cup, 159 years after the first race in 1851 around the Isle of Wight.

*One defender (Alinghi) faces a challenger team (BMW Oracle) in the best of three races off Valencia.

*The first race takes places over 40 miles, 20 miles upwind and 20 miles back, with the second over a triangular course of 39 miles.

*Races begin on Monday, and then every two days after.

*Following legal disputes, this year's event has just one challenger, compared to the usual eight to 10, racing against each other in a regatta.