Ang Lee's work has often been described as cold. The muted, lonesome prairies of Brokeback Mountain (2005), the frozen woodlands and dislocated relationships of The Ice Storm (1997), the stylisation that keeps characters apart in Crouching Tiger, Hidden Dragon (2000) and even the stifling social conventions in Sense and Sensibility (1995) have all served to perpetuate this chilly reputation. And yet the little man in the cosy grey jumper who is perched on the sofa opposite me is anything but cold. He is warm, humble, charming and, above all, intensely passionate about making films.
That passion - in both the physical and the emotional sense - is something he has had to draw on in abundance for his latest feature, Lust, Caution. Lee's first Chinese-language film since Crouching Tiger, Hidden Dragon, it is based on a short story by the acclaimed novelist Eileen Chang and is set in Hong Kong and Japanese-occupied Shanghai during the Second World War. It tells the story of a young woman who uses her talent as an actress to seduce the head of the secret service, who is collaborating with the Japanese, with the intention of luring him to his death at the hands of the resistance. In doing so, she initiates a sadomasochistic game of cat and mouse in which the roles are constantly reversing and nothing, not even her own identity, is certain.
The only place where all pretence is shed is in the bedroom, where three long, graphic and often violent sex scenes play out. It took 12 days to film these exhausting and disturbing episodes, and they have gained the film an NC-17 rating in the United States. This is a huge blow to Lust, Caution's distribution because, given the pornographic stigma that still clings to an NC-17 rating, many cinemas simply will not show the film. But Lee has refused to edit out the sex scenes for US audiences, insisting that they are absolutely essential to a full understanding of the work.
"The whole of the second half of the film is charted by those three sex scenes. I shot them early on in the schedule so they would help me craft everything that comes after. The precise angles of the body help to visualise the characters' emotions and how they relate to one another in the film as a whole, as well as providing guidance to the audience. But thanks to the rating, it will be hard to drag people in to a movie that is seen as the cultural equivalent of a porn film."
The aggressive and demeaning way in which the female lead (played by newcomer Tang Wei) is treated in the film has raised com parisons between Lust, Caution and Bernardo Bertolucci's Last Tango in Paris, in which Maria Schneider is subjugated sexually by a far older Marlon Brando. But Lee denies that his film is misogynistic. "The story is written by a woman from a woman's point of view, and Wong Chia Chi [Tang Wei] is a strong character. I think this provides a fresh angle on female sexuality, especially when contrasted with the political aspect, which is usually very patriarchal. The woman's perspective is like the dark side of the moon: it always exists, but it is never exposed, at least not in my culture."
In the course of the film, Tang Wei's character evolves from naive, orphaned schoolgirl to ambivalent femme fatale under the alias of Mrs Mak. A former Miss Universe finalist, Tang is fairly well known from her work for Chinese stage and television, but had no film experience what ever prior to this. So how did Lee manage to coax such a convincing - and demanding - performance from her? "When I cast her, I couldn't think about whether she was strong enough to take it or not; I just had to believe in her, and hope that belief would become the strength. As long as she wasn't crushed by the work, we just kept building on her character day by day. If she started to get too comfortable with the routine and the abusive nature of my directing, we would have to give an extra dosage of pressure at the end of the week, because she had to be stimulated to make her change and evolve."
It is hard to imagine someone so affable being "abusive". Lee laughs. "It's only abusive on the surface. And anyway, the toughness is mutual. The actors want it as much as I want it. It's not about pleasing me; it's about whether they hit the standard I set or not. And in the case of Tang Wei, I chose her from 10,000 other actresses because I felt she was a lot like me."
According to Lee, it is his identification with, and respect for women that allow him to place them in such gruelling situations. "In my culture, there's a tradition that when you're in an overwhelming situation and you don't know what to do, you put yourself in a woman's shoes. I guess this makes it easier for me in a dramatic situation to identify more with women than with men. I'm not macho, I'm not a Mel Gibson sort of person." In fact, Lee has first-hand experience of what it's like to fulfil the woman's conventional role. After failing, much to the disappointment of his teacher father, to get into university in his native Taiwan, he went to drama school in Taiwan and then completed a Master's degree in film production at New York University, but then remained unemployed for six years. His wife, the microbiologist Janice Lin, was the sole breadwinner for them both and their two sons while he worked as a full-time house husband.
Lee finally got his film breakthrough when he won first and second places in a screenwriting competition organised by the Taiwanese government in 1990. But his biggest break was being asked to direct Emma Thompson's screen adaptation of Jane Austen's Sense and Sensibility. This won him his second Golden Bear, as well as bagging seven Academy Award nominations in its own right. Following a dip in commercial success with his next two films - The Ice Storm and Ride With the Devil - he once again grabbed the world's attention with Crouching Tiger, Hidden Dragon, his revival of the martial-arts epic as a genre, which notched up Oscar nominations for Best Picture and Best Director, and won the prize for Best Foreign-Language Film. But then in 2003 came Lee's part-CGI comic-book adaptation Hulk, a box-office flop that polarised critics and left most audiences baffled and alienated.
Physically and mentally drained, his confidence knocked, Lee considered early retirement, he now admits. Encouragement came from an unlikely source: his father, who had hitherto expressed little more than dismay at his son's chosen career path. "If it was a choice between making movies and doing nothing, he'd probably still wish me to make movies," laughs Lee. "So he made me keep going."
It was fortunate he did; Lee's next film was Brokeback Mountain, the "gay western" that won the hearts of audiences worldwide, as well as a Best Director Oscar for Lee. "After Hulk I was exhausted and felt unhealthy, but then Brokeback really brought me back to life and to love of film-making. I didn't know it was going to be a big success. I thought that people wouldn't pay it much attention. I just wanted to enjoy making that movie because I loved the material so much."
So what next for a man who has covered every genre from period drama to cartoons and cowboy films? Despite rumours on the internet that he has agreed to direct A Little Game, an adaptation of a play by Jean Dell that's the latest project of his long-time collaborator James Schamus, Lee insists he has no plans.
"I have to feel passionate enough about a project before I agree to come on board. But it will most likely be another adaptation." It seems odd that someone with a well-demonstrated gift for screenwriting should be so eager to use other people's material. "I'm quite lazy," the director explains. "I prefer to find a ready-written piece of literature that's already great, and I snatch the idea. I find the writing process very lonely, very painful. I only started out writing because, at a young age, nobody would give me anything to work with. I was just earning my right to direct."
Lust, Caution is a masterful evocation of one of the uneasiest periods in China's history, as distilled in the power struggle between one couple. The measured pacing ensures that every scene, whether depicting the mundane or the melodramatic, is charged with fear and suspense, eliciting subtle yet insightful performances from the actors. Yet Lee fears his efforts will not be recognised at this year's Oscars because of the film's limited distribution and because Lust, Caution has been withdrawn as Taiwan's entry for Best Foreign-Language Film. According to the Academy of Motion Picture Arts and Sciences, "an insufficient number of Taiwanese participated in the production of the film" for it to qualify.
But Lee says he is more concerned that people understand and respond to his film's message than he is with personal accolades. "I want Lust, Caution to provoke closer examination of ourselves - not only our sexual desire or our motivations, but how we see the world. That's 'lust', in Chinese. It doesn't mean just love or sex, but anything with colour, a phenomenon that you see as reality, including emotion that you think is real, a reflection of the truth.
"Not that I provide any answers. But it's an invitation to take a look at ourselves, our rationalities, so we can peel them off to see the subconscious beneath. Everyone has their own particular lust, but let's take a look and see what that is."
"Lust, Caution" (certificate 18) is out now on general release