The film – and the posters, which are still revered by cult film fans – fired up the trashy “Deadly China Dolls” perception of Hong Kong cinema that has always dogged the city’s film industry abroad.

The Post was as confused by Yau’s transition from respectable actress to Category III star as everybody else.

“Has Chingmy Yau forsaken Chinese costume films for throwing off her clothes in Category III teasers?” pondered SCMP writer Brendan Delfino in an article entitled “The naked truth about Chingmy”.

“It is easy to get that impression, given the ‘revealing’ posters of her latest film, Naked Killer,” Delfino wrote.

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“No, no,” countered Yau in an interview, “I’m not heading in the Category III direction. I’m just moving into different areas of acting. I’m not going to limit myself to making the same movies again and again. I’m trying different, more varied roles.”

The Post noted that it had heard Naked Killer was “a startling departure from her previous roles, featuring scenes of lesbianism, and her character’s acute hatred of men”, but Yau, who later accepted her Category III status, was unmoved.

“Even though it’s a Category III film, little of me is seen in the sexy scenes. We discussed these aspects of the film before I started, and we compromised on exactly what I would or wouldn’t show,” she said.

As for the racy poster, she did it for the sake of the movie.

“I really wanted those shots to look sexy, to help make people interested in the film. When the shots for the ads were taken, we had a female photographer, so I wasn’t too uncomfortable posing,” she said.

Yau actually did show quite a lot in the film’s “sexy scenes” – although she never showed everything in any of her Category III films.

“The trouble with a lot of sex and violence films is that there’s usually not enough of either,” wrote Rick Baker and Toby Russell in The Essential Guide to Hong Kong Movies, which has a section devoted to Category III movies. “However, that’s a dilemma that Naked Killer remedies with a vengeance.”

The sex scenes, some of which were trimmed for the international release, are soft porn, and a much-discussed “highlight” of the film is when one of the characters mistakes a dismembered penis for a hot-dog sausage.

Yau’s unrestrained performance quickly saw her become a sex symbol in Hong Kong, and she went on to make more Category III exploitation films like the tawdry and unsavoury Raped by an Angel. This nasty little film was billed as a sequel to Naked Killer even though the story bore little relation to it.

Category III films, which at the time generally mixed soft-core sex, extreme violence, gore and crude humour, were still relatively new in 1992, as the rating had only come into existence in 1988, but the genre was booming.

Along with the voluptuous Amy Yip Chi-mei, Hong Kong’s first modern sex symbol, and Veronica Yip Yuk-hing, the first Hong Kong actress to appear fully nude on screen, Yau become one of the genre’s top stars.

An alleged romantic affair with prolific super-producer Wong Jing, who made a mint by dabbling in all styles of trashy movies, led to suggestions that Yau had no trouble snagging such roles.

Wong sometimes appeared in Yau’s films as an actor, and reportedly protected her, ensuring that there were always some strategically placed props to make sure she wasn’t fully exposed to the cameras.

Yau’s Category III reputation did not hurt her career – in fact, it jump-started it. She was pretty, and that was considered a virtue at the time in Hong Kong, so women didn’t take against her, although she didn’t win a female following like Veronica Yip did when she went mainstream.

She was even nominated for a best actress award at the Hong Kong Film Awards in 1996, for the romantic comedy I’m Your Birthday Cake, although she lost to the eminent Josephine Siao Fong-fong.

But filmmakers were always keen to capitalise on her looks, even for mainstream films. In an interview in 1996, the Post noted that in the promotional posters for her movies, she often appeared in “suggestive or even semi-nude poses”, even if such scenes did not appear in the actual film.

The star was upfront about the reason: “I may look very sexy in some promotional posters, but from a commercial viewpoint, the purpose of that is to attract people’s attention. The image may have nothing to do with the plot. Commercial films have to sell.”

Yau, who said she had always liked to “show off”, started working as a model when she was at school and continued after she left. She appeared in around 100 adverts, publicising everything from food to cosmetics.

She was so successful she became overexposed – clients, she said, claimed that the adverts she appeared in promoted her, and not the product.

When the advertising work dried up, she entered the Miss Hong Kong beauty pageant and reached the finals. She dropped out before the competition ended and started working in the film industry.

“Even though Yau has been in a lot of iconic Hong Kong movies, she was almost never the lead in any of them,” notes cultural commentator and Post contributor Ben Sin.

“But she was in so many Hong Kong movies during the industry’s peak times, she became one of the most well-known faces of that era. Anyone who watched Hong Kong movies during the 1990s would instantly recognise her.”

Absent from the media for a long time, she recently received some press attention thanks to her youthful looks at age 54.

In this regular feature series on the best of Hong Kong cinema, we examine the legacy of classic films, re-evaluate the careers of its greatest stars, and revisit some of the lesser-known aspects of the beloved industry.