You don't need to be of the opposite gender to notice this. Whether mooning over Bruce Robinson in The Story of Adele H (1975) or yielding sweetly to Klaus Kinski in Nosferatu (1979); whether mating with ET's big, bad brother in Possession (1981) or flaunting tarty plastic earrings and cheap, frilly cotton frocks, suckling at her mother's breast and seducing an entire town in One Deadly Summer (1983); whether obsessed, eclipsed and eventually destroyed by her fellow-artist and lover Rodin in Camille Cla udel (1988) or prowling the streets of Paris desperate for a man in La Reine Margot - she makes love marvellously. Typically her characters are unconventional, flamboyant, impulsive, erotically assertive: watching her, you have the pleasurable, unsettli n g sense that she's prepared to do anything. She's rarely seen playing housewives.
But Adjani is a sexy lady who can also act (and of how many female stars can one say that, hand on heart?). She was hand-picked for the Comedie Franc- aise at the age of 17. Barely 20, she was Oscar nominated for her first big role in Adele H (she has since had another, for Camille Claudel). At 22, she cracked the cover of Time magazine, although only, she is quick to point out, the European edition. How did she feel about being an overnight sensation? It was, she says tightly, "embarrassing".
Our interview is hedged about with the usual starry bartering. It's on, then off, then on, in Paris, no in London. No photographer - heaven knows why because, casually dressed in grey leggings, a faux military jacket and no make-up or jewellery to speak of, she still looks drop-dead gorgeous: better, many might think, than in the glossy, slightly impersonal agency portrait we've used instead to illustrate this story.
She'd like to check the copy too, for "factual" errors. "Sometimes one reads things . . . people's imagination is limitless," she observes drily. "Because of today's [computer] technology, misinformation is preserved and you spend your time repeating `NONO NO!' " Questions of control: but Adjani has rather more reason than most to mistrust the media.
Once, however, you have passed all the tests and are ushered into her presence, her commitment is total. Where the standard star interview is a string of brisk, well-rehearsed sound bites, hers (the other cuttings confirm) regularly blossom into long, expansive, intimate and entertaining chats. "Do you think we might have another half-hour?" she asks the publicists politely each time they try to prise her away, as though she were asking them, and me, an enormous favour. She speaks slowly, thoughtfully, deliberately, but - in sharp contrast to her brooding screen persona - with frequent blasts of infectious laughter.
Francois Truffaut wrote, of her work on Adele H: "Isabelle is extraordinary . . . very disciplined and punctual . . . she gives so much of herself that one finds oneself filled with emotion, admiration and gratitude." And it was her support for Margot, abig-budget historical epic set during the bloody wars of religion of the 16th century (she came on board at an early stage), that helped push the project through a long and painful gestation.
"Patrice [Chereau, the director] was boiling with ideas," she says. "I liked the way they were going to do it as a modern drama. Because men are still as bad, as wild, as cruel, as intolerant, as determined to be righteous and to be murderous for the sake of their beliefs. Europe is on fire, and Africa: it's like the planet Earth is having a new wave of madness and distress, and I was intrigued by how we could relate through history to what's going on in the world now.
"Margot is a very juicy legend: such a libertine. And the love she experiences is like a flower growing in this land of blood and death and desperation. If I had to name which character represents hope - if we could all have labels - I would say she represents hope."
Hysteria, neurosis, madness: these states sit comfortably on her. She has gone mad on screen on at least three occasions. "But I never go over the cliff," she says. "I take risks, but I don't lose respect for my real self. Because what's going to happen afterwards, how are you going to get back? Is there going to be a train, or will it be after midnight and you can't go home again?"
She picks her films carefully - which is not to say that there haven't been some fearsome stiffs (Possession, The Bronte Sisters, Ishtar). But her choices are always eccentric, unpredictable. A serious Hollywood hit has eluded her, although she was in the frame for the Glenn Close role in Fatal Attraction. "Another obsessive woman! . . . I knew I could do it, of course. But I was already preparing Camille Claudel."
After Camille she disappeared for four years, to the great dismay of her admirers. "There were a few offers, but nothing substantial," she says. "It's like when people don't ask you to a party, thinking that you get so many invitations. It's funny how people fantasise about your life sometimes. But it's so much quieter than they think."
Last year she resisted attempts to recruit her as a celebrity extra in Robert Altman's Pret a Porter. "I would prefer to hide under my bed! I couldn't believe that all these people said yes. They're so vain! I thought, uh-oh, uh-oh, watch out, he's gonn a chop you up."
Instead, her comeback was Toxic Affair (1993), which she describes as a "feminine, sweetly defectious [sic] comedy". It flopped in France and never opened in Britain, which is a great pity, since it would have allowed us to see another side of Adjani. "People tell me I'm doing all these intense women and that I should lighten up. Then I do a comedy that I'm not happy with and I think "let's go back to heavy, heart-breaking drama; it's so much more fun'.
"I also guess I made a choice: I wanted to get down to my essence and take care of all the people I love: to be there for them instead of having them be there for me." A further leave of absence is indicated, since Adjani (who already has a teenage son with the cameraman / director Bruno Nuytens) is pregnant again with a son by Daniel Day Lewis, with whom she has had a long, if erratic liaison.
At her age, might it not be thought rash to vanish for so long from the public gaze? Whoops, dangerous corner: when that phone call finally comes to correct the errors, it is (and one wonders whether that wasn't, after all, the real purpose of the exercise) also to ask, nicely but anxiously, that I not reveal her age. Then she thaws again: who gives a hoot anyway about the A-list? "Can you imagine?" she says with huge amusement. "After Schindler's List, Hollywood lists. They look at me there as if I'm from another planet. Maybe one year I'll beat Gerard Depardieu and make four movies. But I have no preconceived ideas about how things should be done."
The watershed, and perhaps one factor which contributed to this withdrawal, was an extraordinary and bizarre episode which managed to outshine even the excesses of the British tabloid press: a malicious rumour that Adjani was ill, then terminally ill, with Aids. Begun, probably, at Cannes in 1986, it snowballed over many months until, even as the actress continued to appear in public, going about her ordinary business, she was allegedly admitted into hospital, with precise details of time and place.
Reports of her death were greatly exaggerated, but Adjani was finally forced to appear on French national television: an act, as she pointed out at the time, as demeaning to herself as to real Aids victims.
Part of this is the base, ordinary slander that attaches itself to any successful star. But some, including Adjani herself, suspected racism: her mother is German, her father Algerian: a severe man with whom she had, by all accounts an intense, difficul t relationship. There had been resentment at her public support for the anti-racist movement SOS-Racisme that same year. It was frowned on, too, when she visited Algeria in 1988 to denounce torture, or when she read from The Satanic Verses when acceptinga French Cesar for Camille Claudel. She says she feels distanced from the French and speaks today of her relief at being passed over in a recent search for a star to model Marianne, the national icon.
One regrets that she has not yet realised her full potential. She has worked with some heavyweight names - Truffaut, Polanski, Herzog, Ivory, Saura - but never formed the kind of long-term actress-director partnership which might have given us some trulygreat movies. "Listen: this is my dream; to me this is it, the most wonderful thing that can happen in an actor's life. But you can't put an ad in the paper: `Looking for my soulmate-director'."
But there is time, and plenty, because, whatever her age, she's still positively blooming. "The soul preserves beauty," Adjani says, and perhaps that's one key to her mysterious attraction. "If there's something ugly inside, it will eventually surface, no matter how beautiful you are. I think sometimes I must have a good strong soul, that all I've been through, in films and in life, has been kind to my face."
n `La Reine Margot' opens in Britain next Friday