A cut above the rest

Castrati were poor boys brutally doctored to give pleasure to the rich: it would be perverse to regret their passing. Yet the frisson they provided must have been infinitely greater than that of mere cross-dressing, more akin to kabuki in present-day Japan than to boys playing girls in Shakespeare. Men who were not men, erect but not potent, promising safe pleasures for women - a third sex whose voices were full of magic and mystery. As the pop stars of their day, they often became fabulously rich.

Castrati were poor boys brutally doctored to give pleasure to the rich: it would be perverse to regret their passing. Yet the frisson they provided must have been infinitely greater than that of mere cross-dressing, more akin to kabuki in present-day Japan than to boys playing girls in Shakespeare. Men who were not men, erect but not potent, promising safe pleasures for women - a third sex whose voices were full of magic and mystery. As the pop stars of their day, they often became fabulously rich.

Their voices drew sublime music from Handel and his contemporaries. The only one we have on record - a Sistine Chapel chorister - may convey disembodied passion, but can only have been the shadow of his 18th-century precursors.

How do we know? Well, here is one critic's assessment of Senesino, Handel's favourite: "He had a powerful, clear, equal and sweet contralto voice, with a perfect intonation and an excellent shake. He sang allegros with great fire, and marked rapid divisions, from the chest, in an articulate and pleasing manner... His aspect and deportment were more suited to the part of a hero than of a lover."

According to countertenor Nicholas Clapton, who is professor of singing at Trinity College of Music, comparisons between castrati and modern falsettos - which is what most countertenors are - are otiose. "They produced their sound in a completely different way because, as they never had a change at puberty, they retained the high notes of a boy's voice while developing the chest register of a tenor. This gave them a range with which we just can't compete."

Which makes Clapton's forthcoming exploit at Battersea Arts Centre all the more remarkable. For there he will attempt to recreate the voice and person of the greatest castrato who ever lived.

Farinelli - born Carlo Broschi - was in many ways remarkable, not least because he came from a noble family. Co-starring in 1734 with Senesino, then the reigning champ in London, he effortlessly reduced him to submission.

As an astonished critic noted at the time: "Senesino had the part of a furious tyrant, and Farinelli that of an unfortunate hero in chains; but in the course of the first air, the captive so softened the heart of the tyrant, that Senesino, forgetting his stage-character, ran to Farinelli and embraced him."

As Clapton ruefully acknowledges: "Some of Farinelli's repertoire is beyond my range, which on a good day, with the wind behind me, goes up to a high B. And his flexibility was phenomenal - every bit as remarkable as that of the great coloratura sopranos of the 19th century. That man put trills where most of us haven't got room to put a single semiquaver."

Farinelli is now best known thanks to Gérard Corbiau's stylish 1994 film, in which the problem of Farinelli's range was solved by digitally splicing together a male falsetto for the low notes and a female soprano for the high ones.

But in Farinelli the Castrato, the bloody operation and subsequent imaginatively dreamt-up amorous adventures obscured the more interesting fact that the most celebrated castrato in the world spent the best years of his life administering music therapy to a sad old king at the Escorial.

Ten years ago, Clapton was invited to star in a concert for a group of psychologists in Bologna, at which Farinelli's sojourn at the Spanish court of Charles III was to be musically dramatised. Charles was paralysed by depression, and, all other cures having failed, Farinelli's voice was deemed the last hope. And it worked: night after night he sang, and the king was roused from his lethargy. The Bologna concert was a success: five years later, Clapton was invited back to star in a fully staged version, in which he would play the young singer while an actor played him reminiscing in old age.

Clapton was impressed with the piece, and saw it as an opportunity to redress a musical injustice. "We'd had the Handel revival, but it obscured the fact that there were dozens of other composers turning out wonderful stuff all over Europe at that time." He translated the script into English, and incorporated a lot of extra stuff he'd found, including a piquant episode in which a young Austrian boy came to seek the old man's advice on the voices he should use in his new opera - a boy named Mozart.

All accounts agree on Farinelli's character: cultivated, gracious, and - unusual for a castrato - sexually scandal-free. So what on earth is director Robert Shaw thinking of, casting Richard O'Brien - creator and satanic MC of the Rocky Horror Show - as Farinelli's older self? For that is what's on offer at Battersea next Tuesday. "I didn't want a conventional actor, and Richard is in some ways very close, in our day, to what Farinelli was in his - a cult hero whom everyone loves."

O'Brien is disarming: the script came through the door, his diary had a gap, and it was only two performances. "But as I read it, I found myself speaking the part aloud. The character's a bit waspish, a bit sentimental, but has generosity of spirit. It'll be like spending an hour with an agreeable old gent - like an evening with Ned Sherrin - the same sort of erudite loquacity.

"Farinelli had no sex drive, which left energy for things like literature and art. I'm not going to do much acting. I'll age up a little, but not too much - after all, I am nearly 60. Nicholas, as the younger Farinelli, will have a powdered wig, and I'll have a turban like Dorothy Lamour."

There may also, if the budget runs to it, be a statue on stage, seen through a gauze, to reflect the emotion at moments of high drama. "Nicholas wants a man," muses O'Brien, "and I want a woman, but either way, they've got to have a classical form. I reserve the right to shave the body hair and do the marbling. Though I suppose, if it's a woman, we'll also have to cut her arms off..."

What about Farinelli's operation? "Well, I did originally train as a Method actor, but I don't think it's necessary to go the whole hog on this one, particularly for only two performances." What happens if the show is a hit? O'Brien looks horrified. "We're in trouble. Because there's no way our singer can do more than two nights at a time - it's right at the top of his range, heavy stuff. No, I think the potential audience for this show is limited."

But that was how he and his friends regarded the Rocky Horror Show, and look what happened to that. "OK, I originally predicted an even smaller audience then. But this show's afterlife would have to be on film. Ken Russell could do it - specially the castration bit. He'd have the boy singing on a razor." (And talking of afterlives, the show O'Brien is writing at present is a Rocky Horror sequel.)

Meanwhile, mindful of the fact that his exemplar could prolong an unbroken note for one whole minute, Nicholas Clapton is taking some very deep breaths.

'One God, One Farinelli' is at Battersea Arts Centre, London SW 11 (020-7223 2223) 29-30 Aug