Portrait of a leading lady: Monica Bellucci

Monica was born and brought up an only child in the small provincial town of Città di Castello in Umbria. Her mother Brunella, whom she adores, was a housewife in the traditional Italian mode. 'That's why it's very important for me to be with Deva, because having my mother there was so nice for me.' Her father Pasquale owned a trucking company and was usually on the road. 'But when he was there, he was there,' she says. 'They were both great parents.'

Monica was a bright girl who won a place to the University of Perugia to study law, then swiftly realised she could make a lot more money with greater ease by modelling, a career that also gave her the chance to escape the provincialism of her background, the one aspect of her childhood that she disliked. 'I wanted to get away because I don't like that Italian tradition where the woman has all the responsibility; she's the mother, she looks after the house, she works. I wanted to be independent very young. I never wanted to depend on a man. So I went to Milan and worked with photographers like Bruce Weber,' she says casually. 'I was 18, earning money, living a beautiful life. All my friends were still at university.'

Two years later, despite being the muse of Dolce & Gabbana, she was bored. 'Modelling wasn't enough as a form of expression. As a model, you are supposed to be quiet and do what you are told. That wasn't me.' She was picked for a small role in Francis Ford Coppola's 1992 film Dracula as one of the vampire's sexy brides, and was herself fatally bitten by the acting bug.

'It was a hard decision. I didn't know what would happen, but I was so curious. I went back to Italy, took acting lessons, but nothing happened to me the way I wanted it,' she admits. 'For them, I was just another model who wanted to be an actress.'

It was only when she left for France that her career took off. She won the role of Lisa in the stylish arthouse hit L'Apartement and bagged herself a César (Best Supporting Actress). 'After that, I never stopped working,' she says simply. Refusing to stereotype herself either as a sexpot or as a star of independent film, she merely accepted parts in anything that took her fancy, from blockbusters such as The Matrix Revolutions to Astérix & Obélix.

Of course, the fact that she's married to Cassel, granite-featured star of innumerable French thrillers and Ocean's Twelve, hasn't hurt her career. France's equivalent of Brad Pitt and Angelina Jolie, the golden couple are known simply as 'Les Glamours'.

They met on the set of L'Apartement, but it was far from love at first sight (even for him). 'He came with no hair to the test,' Monica complains. 'And he was pretentious. He'd done La Haine, but it hadn't come out yet. I said to my agent, "Why do you have to choose this guy? There are so many sexy actors." And he said to the producer, "Why do you have to take this Italian model with all the great French actresses there are?" '

She gives an elegant shrug of her shoulders. 'Maybe we were already attracted. When we were in rehearsal, I felt there was something going on.' They have been together ever since, marrying in 1999. 'My God! Fourteen years!' she says. 'To me, normality is being alone. It's a miracle to stay with anyone.'

It's even more of a miracle in the film world, of course, but the pair make things easier by working together when possible. They have made eight movies together, including Irréversible (her rape scene apparently reduced him to tears). 'We know each other, so we protect each other,' she says of their working relationship. 'And we don't talk much about work at home.'

She is pragmatic about their future prospects. 'I don't know how it will be tomorrow because we all change and grow up in different ways,' she says. 'But I met a young boy 14 years ago, and I like the man he became. He's growing up in a beautiful way. I think he's a sexy man, Vincent. He's a special-looking guy. And he makes me feel safe: if something happened to me, Deva has someone who's there for her, who's going to protect her.'

The trio lead a peripatetic life, shuttling between homes in Chelsea, Paris and Rome (naturally, Deva speaks all three languages). 'Next year, my baby is going to go to school, so we have to decide where our base is going to be,' says Monica. 'It won't be easy because the choices I make are a bit all over the place. I've got one film in Italy, one in France and one in the US, so this is complicated.'

Indeed, at 45, when most Hollywood actresses are looking to diversify into property, Monica is busier than ever. This year, she has appeared in Rebecca Miller's The Private Lives of Pippa Lee and Don't Look Back with Sophie Marceau, as well as two Italian films, and next year will see her starring opposite Nicolas Cage in The Sorcerer's Apprentice as his long-lost love. 'It was a chance to make a film that my child can watch,' she explains fondly.

But moving to LA is definitely not on the cards, whatever the advantages might be for her career. 'They never stop working,' she protests, sounding more Italian than ever. 'The energy is incredible. That's why, after a little while, I have to come back to Europe.

'And I get bored at parties. I like to stay with my friends, have a nice plate of spaghetti and a glass of wine, and a real conversation. It's interesting to work in America but really I'm very Italian.' You don't say, I think, as she rises to her high heels and undulates away, with every male eye in the room watching intently.

Hair by John Nollet. Make-up by Letizia Carnevale using Dior Autumn Look 2009. With special thanks to the Hotel Pavillon de la Reine, 28 Place des Vosges, Paris (00 33 1 40 29 19 19; pavillon-de-la-reine.com)