The virtues of Weisz

When she collected the prize, she was seven months pregnant and on 31 May, she gave birth to their son Henry Chance Aronofsky. Now she's back to her curvaceous movie-star figure after a pregnancy practically lived out on the red carpet. Has the baby made a difference? "Well, it certainly gives you more empathy for all the mothers in the world," she says. "You realise that everyone you see on the street was a baby once. You see a politician on TV that you despise and think that he was a little baby once. I mean, Bush was a baby."

The baby did get Weisz into trouble earlier this week, though. Was she irresponsible or just impetuous when she admitted that she didn't see anything wrong in drinking wine after the third month of pregnancy? The experts are still rowing about it. But Weisz thinks it's "fine". They do it in Europe," she says. None of us should be surprised by this outspokenness, or Continental outlook. She's always been a firey creature. Right back to the when she was expelled from two schools - before she ended up at St Paul's, doing quite a bit of modelling on the side. She took a degree in English at Cambridge, only to plump for acting, instead of following the career in law her parents had hoped for.

Her family of strong personalities may lie at the root of her spirited ways. Her parents are both Jewish, as her surname (pronounced "vice") would suggest. Her father is a medical inventor who fled Hungary to England to escape the Nazis and her mother is a psychotherapist who fled from Austria. They divorced in 1986 when Rachel was 15 and her father remarried another therapist.

"They're not sheep, my parents," she smiles. "They don't follow the herd. They are very opinionated and they always encouraged debate at home. Other people might think it was arguing but we are always involved in some kind of discussion about everything, and were all very passionate. My mother is half Italian and it drives her nuts that English people are so reserved.

"There was a lot of storytelling, reading and going to see plays and ballets and films when I was growing up," she continues. "I would say the tone was quite operatic. It was very natural for me to go into a life of telling stories."

While telling the stories - from a mini-series with Ewan McGregor, to a full-frontal nude scene in Stealing Beauty - she dated a string of high-profile names, an eclectic mix which included director Sam Mendes and actors Alessandro Nivola and Neil Morrissey. But then, in 2001, she met Aronofsky. He is now 37 and one of Hollywood's boldest talents, director of Pi and Requiem for a Dream.

"We share the same values," she says. "Neither of us is very materialistic. When I met Darren he was already in his thirties but he was still living like a student. He lived in a fifth-floor walk-up in a tiny place with no furniture and a little table where he wrote the three films. I got him out of that apartment. We live somewhere with furniture now."

But what appeals even more is his strong personality, unintimidated by the fiercely independent Oscarwinner sharing his life. "He's from Brooklyn and he's got a very strong Brooklyn mom who is a fabulous personality and a force of nature. I think when men have really good relationships with their mom, they can be very cool with women being strong. When I am being particularly strong about something, he whinnies and does this big horse thing like I'm a wild stallion about to take off."

So did he let her run free on the set of The Fountain? "Not at all!" she laughs. "He doesn't like improvisation at all." "I tried it, but he wasn't keen."

Nonetheless, watching him at work changed the dynamic of their relationship. "I think, as a woman, to see a man be really good at something, really talented, is very sexy. Women love talent. I don't know if men do. Or I'm not sure they are so interested. To see Darren get such great performances out of everybody ..."

Shooting for The Fountain finished 18 months ago, so, quite by accident, Aronofsky's dream project stars an Oscar-winner.

"Of course, I didn't know The Constant Gardener would lead to all that recognition," she says. "And you never know how things are going to resonate. How the film is going to come together is a mystery, isn't it? Alchemy."

Alchemy has certainly raised this film's profile and Weisz's choice of movie role. Earlier this year, only three months after giving birth, she was in front of the cameras again in the first English-language film by the brilliant Hong Kong director Wong Kar-Wai, the road movie My Blueberry-Nights. She has a small role opposite singer Norah Jones, Jude Law and Natalie Portman. She has shot a New York comedy called Definitely, Maybe. And next spring, she takes on her first leading role since the birth of her baby in a Europe-set conman "dramedy" called The Brothers Bloom.

She and Aronofsky have no plans to work together again. "I think we'll have to stagger our work now to keep the family together, but if we work together again it would be perfect because the three of us would be in one location."

"But I would never abandon England," she says. "All my family are there and all my friends who I grew up with. I've only been with Darren for five years, whereas before my whole life was in England."

Nor do she and Aronofsky have plans to marry, even though the couple got engaged in June 2005. "We've spent a lot of time dreaming up different versions of a wedding - what kind of ceremony we would have, where it would be - but we're still dreaming. We haven't found the time to actually do it. I don't know how much it matters to us right now."

"Like in the film, there's a part of me that thinks we were meant to be together. But there's another part of me that knows any relationship needs work," she muses. "My dad has always said to me, and he came from a failed marriage, that relationships are very hard."

Weisz smiles that bewitching smile. "It's not like in the movies."

The Fountain is released next February.