Knitting?" She explodes with heavy Eastern European emphasis in what could equally be ignorance, contempt or indignation (hard to work out). "What is knitting?" I go into mime-mode and attempt to demonstrate a woolly jumper in the making. I had merely asked how she amused herself when she was not performing on the world's most celebrated opera stages. Cooking? Aerial photography? Er, knitting? (Dame Joan Sutherland was known to knit backstage when she had time to kill between appearances.)
"It's rare that I am offstage very long," says Gheorghiu, with the certainty of one who knows her status in the business. And then recognition dawns. "Ah ... Knitting! God no. When I was a child I knit once. Terrible. It didn't fit." And she explodes again, but this time (I'm relieved to say) with laughter.
Of course, I should have known better than to ask. Divas do not knit (Joan Sutherland excepted), and Angela Gheorghiu is a diva of the first order with all the word implies, good and bad. That most people, these days, tend to regard diva-dom as bad - a risibly outmoded lifestyle choice of tantrums and tiaras - doesn't worry her. She grew up in Romania; she never saw Miss Piggy on the television; and she doesn't do irony.
"When people come to see Angela," she says, "they come to dream. They need this. How can I be a normal person? Why pretend I'm not something different? I am different."
And when others complain that grand behaviour, diamonds, furs and Rolex watches (Gheorghiu is an official "Ambassador" for Rolex) are politically unhelpful images for an art form dependent on public subsidy?
"Let them complain. I am an artist, I have no time to think about politics. When people say, 'We don't want divas any more,' this is only because they are not the diva. Jealousy!"
It's undeniable that Gheorghiu gives her critics plenty to be jealous of. She's been outrageously successful. Her official website (she has registered her name in order to close an unofficial site that didn't please) describes her as "the world's greatest living soprano"; and in earning power if nothing else, that's probably correct. With the Sutherland / Caballe generation out of the ring, and Kiri te Kanawa close to retirement, Gheorghiu rules - at least, over the core Italian lyric repertory from Verdi to Puccini and the French 19th-century arena. She hasn't so far ventured into German opera though she says the time will come. And with a growing strength in Donizetti and Bellini, she's the kind of singer opera houses chase.
When she stars in Puccini's La Rondine later this month at Covent Garden, it will mark 10 years to the day since the chase began in earnest. On that same stage, in extraordinary circumstances.
It was in November 1994 that a little-known soprano with a name that people mispronounced (thinking the Gs were soft rather than hard), appeared in a new production of Verdi's La Traviata and redefined the cliché "overnight success". In living memory there has been nothing quite like Gheorghiu's triumph at that opening. BBC TV executives were in the audience and, next morning, cleared their schedules for a broadcast - the kind of gesture you associate with the death of monarchs. Decca Records swept in and, in a matter of weeks, turned f around a recording that would otherwise have taken months. And the seriously photogenic Gheorghiu - looking as amazing as she sounded, with a falling mane of jet-black hair and legs like mating eels - filled spreads in almost every British newspaper, alongside eulogies more lovesick than evaluative.
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Critics duly noted that her voice was individually distinctive, with a glistening liquidity, a strength across the whole range, top to bottom, an immaculate legato - all of which was true. More to the point, though, was the fact that as a singing-actress, Gheorghiu stole their hearts as no performer had in years. The usual comparisons were made with Callas (everybody gets compared with Callas), but for once they had a point. She seemed to be a star of that dimension.
It was all the more extraordinary for someone whose experience was so limited (the Traviata was her fourth professional stage-job) and whose background so unlikely.
Gheorghiu was born in 1965 in Adjud, a small town in Ceausescu's closed Romania, where food was short and life was hard. Her father was a train-driver, her mother a dress-maker - which meant, as she says, "I at least looked good, even if I go hungry. Always beautiful gowns, copied from the TV stars."
No doubt the frocks gave her ideas because, she says, "I always knew, from age six, that I was an artist. That I had destiny. Never for a moment did I doubt this."
The undoubting Angela pursued her destiny at 14 to a music boarding-school in Bucharest, and then the Bucharest Conservatory. She graduated with a student La Boheme in 1990. And by that time fate had genuinely intervened because Ceausescu fell in 1989. The borders opened, travel to the West became a possibility, and Gheorghiu seized the moment. Aiming always for the top, she flew to London to audition for Covent Garden's head of casting Peter Katona.
It was Katona who effectively discovered her, although when I put it in those terms she insists it was the other way round.
"I discovered him," she says. "On street. I ask everyone where is the stage door of opera house and they say, 'Go here, go there'. Then I ask one person who says, 'Along here, ten metres'. Then I go and sing and who am I singing to but this same man - who remembers me, I think, because I'm dressed in red." One of mother's.
Between the frock and the voice she made an impression, and Katona offered her the role of Mimi in a revival of Boheme: her first professional opera booking. "But I wasn't sure I was ready for this. So I ask to start with something smaller, and I also look for something in less important house, not London, for experience."
The result was that she sang L'elisir d'amore in Basel; then, in 1992, Zerlina in a Covent Garden Don Giovanni, followed by Mimi in Boheme. It all went well, and her career was launched. But it took another fateful intervention to exalt her to true diva-status.
The pre-eminent operatic maestro Sir Georg Solti had never conducted La Traviata and thought it was time he did. Coming to the score at such a late stage of his career, he wanted it to be an event. And he wanted someone special for the title role. Someone out of the ordinary.
He auditioned Gheorghiu and decided she was the one - for reasons that his widow Valerie Solti remembers as "her purity of approach. She was a sort of innocent at that time, though not in a negative sense. She had this quality of being from another world, a sort of spirit being. And he was entranced by her. From the moment when she came out on the opening night in that Elizabeth-of-Austria dress, it was like a fairy tale. Something you never forget."
Covent Garden certainly never forgot, building a special relationship with Gheorghiu through the years to the point where she is now its lyric soprano of choice. Productions, like La Rondine, are built around her. Years of scheduling, in fact, are built around her. She is box-office.
But Gheorghiu's market value doesn't just relate to what she does onstage. Her offstage life acquired the fairy-tale touch too when she married her leading man, the dashing, heart-throb tenor Roberto Alagna. It was a romance straight out of Mills & Boon, with all the necessary accoutrements of glamour, stealth and triumph over tragedy.
They met initially at Covent Garden, singing in that 1992 Boheme; and as Alagna admitted to me when I asked him recently: "We were in love from the first instant. I touched her hand in the 2nd Act and it was like a coup de fou. I felt electricity in all my body, something very strong."
The problem was that both were married - Gheorghiu to a plumbing engineer back in Romania, Alagna to the mother of his daughter back in France. So for a while, at least, the electricity was put on hold and no one knew about it. Then, in 1994, Alagna's wife died from a brain tumour. It was traumatic but it left him free for Gheorghiu, who then quietly put aside the plumbing engineer. By 1995 they were engaged. And in 1996 they were married, showbiz style, by Mayor Giuliani in New York. The papers loved it.
But what the papers loved even more was that the newlyweds had started to behave imperiously. Stories circulated of absurd demands, of towering rages, stormings-out, and massive vanity. And there were nicknames: the Ceausescus, Draculette, Bonnie & Clyde.
"At first, this shocked me," Gheorghiu says, "then people say: 'Congratulations, now you know journalists and the lies they write.' Now I understand. I know the price of being Angela."
She says this with a curious curdled sweetness that I know won't come across from reading her in print. And it occurs to me that half the problem with her public image is linguistic. She speaks English in a crazy, energised staccato, every sentence ending with an exclamation mark. Reduced to print it gives her a veneer of brazenness that doesn't necessarily run deep. When she appeared on Desert Island Discs last spring, she specified an English language primer for her chosen book. It wouldn't be a bad idea.
As for the bad behaviour - touching up her lipstick in the middle of a Verdi Requiem, demanding personal stylists for a Radio 3 interview, refusing to put on unflattering wigs and costumes - much of it has entertainment value; and even the worst offences can be f explained as the response of two people from humble backgrounds (Alagna was singing in a pizza bar before he became famous) coping badly with their sudden wealth and power. Of all the labels pinned to Gheorghiu and Alagna, the most accurate has probably been "opera's Posh & Becks", which also fits the sentimental family attachments. Gheorghiu is now mother to two step-children: Alagna's daughter and the daughter of her own sister who died several years ago in a car crash. And though they collectively make what Gheorghiu calls an "elastic" family - one child at school in Britain, the other in France, and both parents based in Switzerland but constantly on the road - there does seem to be a real and rather touching bond between them all.
"Angela is a strong personality but I know her sweetness," says Alagna loyally. "She has a big heart, she is a good person, and she's a fantastic mother. Believe me."
Oddly enough, sitting with her on a horribly expensive sofa in the no doubt horribly expensive flat in Kensington she's renting for the run of Rondine, I can believe it. She's formidable but funny: not by any means the innocent from 10 years ago, but there are girlish moments when the slightly scary glamour slips and she pulls adolescent faces.
She pulls several when I raise the matter everybody else does: her continuing involvement with Alagna. There are endless rumours of a break-up. And the search for omens has been fruitful since Alagna quietly switched recording labels, leaving EMI for Deutsche Grammophon. The significance (perhaps) of the move is that Gheorghiu left Decca to join EMI so she could collaborate more easily with her husband on recording projects. But there haven't been any CD collaborations for a while now, and no more are planned. What this means is anybody's guess.
Another cause for guesswork is the fact that Alagna won't be singing alongside her in the Covent Garden Rondine. The show was purpose-built as a vehicle for them together. It was one of their supreme successes last time round, with a CD issue that won international prizes. You'd have thought this first revival would be wanting to repeat the circumstances.
"Nonsense," Gheorghiu tells me sharply. "The only reason Roberto doesn't sing is he can't do all the rehearsals. Why? Because he makes his first disc for DG. That's all. Is our marriage over? - I hear this from the first year we are together. I tell you, we have our life, our family, but we are not Siamese. Sure, I've only done Rondine with Roberto and it's special for us: without him it won't be the same chemistry. But let's see. I tell you afterwards."
At this point in our interview she's getting tired. She has a cold (the singer's curse). She dabs her eyes. Before I go I can't help asking the inevitable: Angela ... any regrets? Any slight reservation about diva-dom, publicity, the opera world?
"God no!" she perks up. "I am all the time happy. I'm not thinking: 'Oh, why this, why that.' I love to be on the stage, to look beautiful, have nice costume, nice roles, and be applauded. We are artists because we need this. I don't want to sing in my bathroom where nobody hear."
'La Rondine' is at the Royal Opera House, London WC2, from 12 to 26 November. Box office: 020-7304 4000; or www.royalopera.org
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