While set in the early 20th century, the film is a thinly veiled critique of the collective hysteria which sustained the many waves of social upheaval throughout the 61-year history of the People's Republic - whether it be the intense purges which marked the Cultural Revolution, or the unfettered pursuit of money as the mainland lurched towards capitalism during the past 20 years.

Lau's character is the epitome of such opportunism: devoid of principles and scruples, the mayor's wife is content to 'let the bullets fly' before emerging to side with the victors so as to ensure maximum economic gain.

'It was a time when people were faced with all these different possibilities,' Lau says.

'It's all about using your abilities to survive and prosper. I think back then women did not have that much standing in society, but [my character] was the kind who's ambitious and knows clearly what she wants ... and her way of doing it was to make use of men to find more money and pursue her dreams,' the star says.

With Lau, Jiang has found someone very much in the know about the joys and perils of such a desire for self-fulfillment in modern-day China. Born in 1965 in Suzhou - where she spent the first 15 years of her life - the actress was well aware of how people looked after themselves during the Cultural Revolution, and how the same people adjusted to life when Deng Xiaoping's open-door policies in the late 1970s set the country on the road to a market economy.

On moving to Hong Kong in 1980, Lau spent her formative years in the thriving capitalist bastion, where a greed-is-good ethos transformed the city into a flashy metropolis famous for soaring property prices, a consumption-driven culture, and gaudy mass entertainment - which Lau became a part of when she started making television serials and films in the mid-1980s.

Now spending a lot of her time on the mainland, Lau is very visible as one of its best-known celebrities. When not making or promoting films - and she's been doing much less of that, having appeared in only five productions in the past five years - she's usually seen fronting publicity campaigns for lavish lifestyle products or attending high-society events.

Lau says she admires Jiang - who is three years older than she is - because his films draw from the same memories of a country swept along in extreme social changes. She says, for example, she was mesmerised by Jiang's previous film, The Sun Also Rises, which reminded her of her childhood years in Suzhou, where she joined the Little Red Guards with her classmates.

Arriving in Hong Kong in 1980, Lau - who couldn't speak Cantonese then - was subjected to a severe bout of culture shock. 'I was a very active student who did well in my studies on the mainland,' she says. 'I was deemed good leadership material - and then suddenly here I was, helpless about my life. I hated the air here which was filled with petrol fumes, and there was such a racket all the time. There wasn't much appreciation of mainland immigrants. I felt so out of place.'

Lau enrolled in TVB's artist-training programme. 'I was just looking for a job. You know, I was quite a renowned performer back in Suzhou - I was picked to join the official theatre troupe in the city's Palace of Culture, so I guess if I had to fall back on the one talent I had, acting would be it.'

Having first starred in television serials - her breakthrough role being one in Police Cadet, in which she worked alongside her future beau Tony Leung Chiu-wai - Lau made the then-expected transition to film. Her stock began to rise in the early 1990s with a string of performances which were rewarded with best actress nominations at the Hong Kong Film Awards.

Now her collaborations with mainland filmmakers have brought Lau's life full circle. 'In fact, my mind still processes everything I read in Putonghua,' she says. 'It's true that the schooling I received here influenced me a lot, but I still think Putonghua sounds much better than Cantonese. But I still love Hong Kong more than the mainland as there's more of an order here and people who are ... well, it's a more civilised place.'

Does she ever feel nostalgia for those simpler days growing up on the mainland? 'But society has to progress, doesn't it? If things had remained the same as they were in the 1970s or 80s, it would be abnormal. It's just like in Bullets, in the scene where this train is shown having to move onwards, because there's no turning back.'

Now well-ensconced in the country's social and cultural aristocracy, this star is not for turning either.