Zhang Weiping, one of the film's investors, and Director Zhang Yimou at the opening ceremony. [Sina]

Filming for Zhang Yimou's latest project, Thirteen Girls in Jinling City, began yesterday in Nanjing, Jiangsu Province. His first war film, Zhang is keeping details about the film to a bare minimum.

Based on a novella by Chinese-American writer Yan Geling, the film tells the story of 13 prostitutes who broke into a church for refuge in Jinling (present-day Nanjing), the Chinese capital during World War II. They are later joined by Chinese soldiers who survived a battle with the Japanese.

"Nanjing is a place of victory and pride," said Zhu Shanlu, Nanjing's party secretary, at the film's opening ceremony. "At the same time, it's a city that once bled in wars. The film will show the struggles and courage of Nanjing citizens during wartime."

The 13 young actresses who play the prostitutes, and whom Zhang and his team spent two years looking for, have not been identified.

"They will be dressed in different and fancy coats and carry classic leather suitcases from the 1930s," Zhang said. "When they walk out in a charming and fascinating manner, you will believe that they are the women of that time."

Production costs for the film are estimated to be 600 million yuan (US$90.6 million). Hollywood actor Christian Bale will play a missionary, and Chinese star Tong Dawei will also star.