HONG KONG filmmakers have never been big on historical films. They cost too much, take too long to research and shoot - and are simply not commercial enough. So a sweeping epic about three controversial Chinese sisters, requiring two years of exhaustive research and costing $50 million, couldn't and wouldn't be done, they said. Director Mabel Cheung Yuen-ting proved the naysayers wrong when she made The Soong Sisters in 1995. The 144-minute version is one of the few, if not only, records of the lives of these three most remarkable sisters. The story of the Soong sisters - Ai-ling, Ching-ling and Mei-ling, who died last week at 106 - was one that needed to be told. And to commemorate Mei-ling's death, Hong Kong film-goers are being treated to a special one-week screening of the film. Ai-ling was the wife of wealthy industrialist and former Kuomintang finance minister H. H. Kung and became one of the richest and most powerful women of her generation. Ching-ling married Sun Yat-sen and essentially became first lady of the Chinese republic after the overthrow of the Qing dynasty. Mei-ling's fate lay with military leader Chiang Kai-shek, who would go on to found Taiwan's Nationalist government. 'I never set out to make a historical epic,' says Cheung, who researched the sisters with her scriptwriter husband Alex Law Kai-yui. 'I just thought it was an interesting story of three women, but when I really started work on it, I had to ask myself if I was crazy to even attempt it.' Cheung and Law went through more than 200 books on the sisters and found just as many versions of the 'true story', depending on the political affiliations of the writers. Ai-ling (played by Michelle Yeoh Choo Kheng in the film) and Mei-ling (Vivian Wu) - viewed as a capitalist and a traitor respectively - were barely mentioned in mainland history books. Many Taiwanese, on the other hand, had never heard of Ching-ling (Maggie Cheung Man-yuk). 'There is no absolute truth, even in history books. History depends on who is in power. In the end, we wrote own interpretation. I don't claim my version is the true version. It's just my interpretation of the history. We also have to give them the respect they deserve,' says the filmmaker. Cheung and Law finally found the 'history' they were looking for in the New York Public Library, which housed personal letters sisters wrote to each other, friends and teachers. 'We wanted to see the private side of these sisters and what their relationship was like after their political affiliation took them separate ways. The letters we found at the library shed a lot of light on that,' says Cheung. The correspondence between the sisters - always written in English - showed they remained close. Another that Mei-ling wrote to an American friend while she and Chiang were fleeing to Taiwan revealed how her husband would pick roses for her every day so she could have them by her bedside when she slept. 'Mei-ling's marriage to Chiang had always been viewed as a political affiliation. In many versions, Chiang was just waiting to divorce her five years later and take back his second wife. But this letter showed that they weren't just that.' The one thing Cheung and Law never achieved was to meet the woman at the centre of their work. Already in her late 90s when they started the project, Mei-ling refused to give interviews. Securing the film's released was another trial, when, as one of the first Hong Kong-China co-productions, it fell foul of mainland censors, who objected to a scene in which Mei-ling pleads passionately with the Chinese army for the release of her husband in Xian. It took more than a year of negotiations before the film could finally be released in April 1997 without the Xian footage - which has since been lost. Producer Ng See-yuen claims Mei-ling saw the film on DVD and said it was 'quite well done', but Cheung never heard from the former first lady personally. 'We had a charity premiere and invited her. She didn't come, but sent her lawyer along. The lawyer seemed to enjoy the film,' the filmmaker says. 'The only lament I have is that Soong Mei-ling lived through and witnessed so many historical events, but never left behind any official audio or visual documentation of her feelings about them.' The Soong Sisters (in Putonghua with Chinese and English subtitles) is screening at UA Pacific Place.