Now Nicholson has allowed the film to be reissued and it will be shown at Britain's National Film Theatre this month before being released on DVD. In an interview on the DVD Nicholson recalls how, in one scene, he had to hold Schneider upright because she was so zonked on painkillers. Despite that, and despite her years on heroin and cocaine, what you notice about her in person is that she still has a faint glow: a warmth, a sense of humour, the calm acceptance of someone who has been there and done it all.

And she has - simulated anal intercourse with Brando, shared a house with Brigitte Bardot, committed herself to a Rome mental asylum, slept with women and men (though she dissolves in giggles at the idea she might have slept with Nicholson) and come out of it all to find true love. But she would not make Last Tango in Paris if she had her time again. "No," she says in her French accent, shaking another cigarette from the packet. "I would have said no. I would have done my work more gradually, more discreetly. I would have been an actress, I think, but more quietly." Bertolucci offered her the part after seeing her picture in a modelling book; even then she was living life at full tilt. She had been raised by her mother, Marie, near the German border in France and had left home after an argument with her at 16. In Paris she survived on handouts from her grandmother and bits of film and modelling work. Her father, Daniel Gelin, was there, too, and already a famous actor. He made no effort to look after his daughter when she turned up homeless.

Brigitte Bardot came across Schneider on the set of one of her films and was horrified she was so unprotected. She took her in, and it was Warren Beatty, visiting the house, who insisted his agent sign her up. "He called William Morris and said, 'You must take this young actress, she's so incredible', and I hadn't done anything!" Schneider says, laughing. But the same agents were horrified when she didn't want to do Last Tango. "They said, 'You're crazy, you have the main part with Marlon Brando!' But I had the feeling that, you know, I would have some problems afterwards. The humiliation was very strong. Marlon said he felt raped and manipulated by it and he was 48. And he was Marlon Brando!"

The film tells the story of a young French girl and a middle-aged man who meet in a dilapidated flat in Paris to have anonymous sex. It broke taboos and its distributors were prosecuted for obscenity. But Schneider says the infamous scene in which Brando sodomises her character with the help of some butter was not in the script. "Marlon had the idea. When they told me, I had a burst of anger. Woo! I threw everything. And nobody can force someone to do something not in the script. But I didn't know that. I was too young. "So I did the scene and I cried. I cried real tears during that scene. I was feeling humiliation. Then six or seven years ago I heard the character I played was supposed to be a boy. That maybe explained it." She lets out another husky laugh. She was headstrong, "crazy", when the film was released. She announced in interviews that she had slept with 50 men and 20 women and was incapable of fidelity. "I've tried heroin," she blithely told a tabloid in 1973, "but I throw up when I take it."

But now she says a lot of that was made up. "It was a joke! Because the press are so, because I was that sexy bimbo, so, 'Oh, she must be hot'. And they were talking about my private life, and I was, 'Yes, I had 20 women and 50 men, blah, blah, blah', and they wrote it down. It wasn't real." Three years after Last Tango in Paris came The Passenger. "I've made 49 movies now and it's the dearest to my heart," she says. "When Antonioni saw Last Tango he understood what I had been through. I had that temper, but the girl from Last Tango was far from what I was. She was going with an old man and was very liberated, which I wasn't, you know.

" Last Tango was a lot of suffering, a lot of compromising. I only understood what the movie was about many years later. It stands because it's Marlon and me and because it's 1970s, but somehow it's aged a little, it's kitsch. Compared to The Passenger it's dated. I think Bertolucci's not a real maestro like Antonioni was. He [Bertolucci] was manipulating everyone on set. I'm not friends with him." It was after The Passenger Schneider "fell", as she puts it - became addicted to heroin, began walking off film sets (one, Caligula, she rightly felt was basically porn). She became uninsurable and unemployable. She moved to California for a year but found the same decadence and cynicism. "So I got a pick-up truck and I went to the Hopi, the Navajo, that was my interest, going to Red Indian reservations. "I was a junkie," Schneider says. "I have no nostalgia whatever for that. I lost a lot of friends who were more fragile - good actors and good artists. In my case it was a kind of suicide, because I was unhappy in my private life. But then I met an angel - who I'm still with today - and I stopped!" Who did she meet? "An angel. That's my secret garden. That's private. I don't say if it's a man or a woman. But it was in 1980 and we're still together. So I have equilibre."

These days she lives in Paris and in her spare time she runs an organisation called The Wheel Turns, which takes care of ageing actors, dancers and performers. Apart from working with Bertolucci she seems to have no regrets, and when I ask why she never married or had children she gives a husky laugh: "In another life!" she says.

Telegraph, London