Documentary on Rape of Nanking disturbing for the filmmakers

Bill Guttentag remembers the moment while filming an interview with a survivor of the Rape of Nanking when the interpretation abruptly stopped. He thought the crew had hit a technical snag; the glitch, it transpired, was due to something much more human.

'We realised later that the interpreter was crying and she couldn't continue,' said Guttentag, who with his co-director Dan Sturman and co-producer Violet Du Feng spent three weeks in Nanjing interviewing 22 survivors for the documentary, Nanking.

'I remember thinking that when it affects the interpreters that much - when they already knew - it's going to have the same effect on audiences.'

And it did. Nanking - which was initiated and funded with US$2 million by AOL vice-chairman Ted Leonsis - received rave reviews when it premiered at the Sundance Film Festival in January. It will make its premiere outside the US at City Hall today as part of the Hong Kong International Film Festival.

In the documentary, the weeks of rape and pillage that the Japanese imperial army committed when it took Nanking in December 1937 are seen through the efforts of expatriates who attempted to set up a 'safety zone' for the city's inhabitants.

Hollywood actors - such as Woody Harrelson, Mariel Hemingway and the young Chinese-American star Michelle Krusiec - read from diaries and documents left by the expats. Their performances are interspersed with archived film footage from 1937 but it is the interviews with the survivors that provide the film with its most heart-wrenching moments.