One of his generation's most important documentary filmmakers, director Wang Bing is at the height of his powers in 'Three Sisters'. The film introduces viewers to 10-year-old YingYing, 6-year-old Zhenzhen and 4-year-old Fenfen, who live alone in Xiyangtang, a tiny rural village in the high mountains of China's Yunnan province. Their father is away working in the city; their mother left the family long ago. The girls help their grandfather or aunt in exchange for meals. They spend their days at gruelling tasks: herding sheep, goats and pigs, searching for firewood, collecting dung. Games are few and far between. The eldest, Yingying, is her sisters' primary caretaker, shouldering responsibilities far beyond her years. Wang's hand-held footage beautifully captures the region's dramatic landscapes and plunging, mountainous scenery in 'Three Sisters', an essential part of the international film canon.