Though it's a work of nonfiction, "Nanking" follows the "Schindler's List" model in using a story of survival and individual heroism to shed light on the unspeakable. Before the Japanese invaded the city on Dec. 13, 1937, Nanking, then China's thriving capital, was home to numerous European and American expats -- 22 of whom chose to stay behind to help the poor and dispossessed who were unable to flee the city in time. Their excerpted writings, as read by a group of actors, serve as the film's narrative framework.

Rather than relying solely on voiceover, directors Bill Guttentag and Bill Sturman (who scripted the film's text with Elisabeth Bentley) have thesps address their words directly to the camera. The prominent figures include Minnie Vautrin (Mariel Hemingway), head of a Christian missionary college; John Rabe (Jurgen Prochnow), a German businessman who attempted to use his Nazi Party influence to stop the carnage; minister John Magee, who set up a hospital to care for the wounded; and missionary George Fitch (John Getz).

Together, they established a makeshift safety zone that spanned two square miles and provided refuge for some 200,000 civilians (and soldiers pretending to be civilians). Although the Japanese soldiers managed to breach the zone, claiming to be in search of Chinese troops but killing indiscriminately, "Nanking" remarkably details how a few vastly outnumbered Westerners managed, to a certain extent, to keep their enemies at bay -- even suggesting that the presence of foreign onlookers stirred fear among the Japanese ranks.

Still, it's impossible to feel much uplift, given the film's unsparing account of the atrocities and the intensity with which they seemed to escalate before the violence subsided in March 1938. While the most notorious statistic may be the 20,000-plus women and young girls who were raped during the occupation, the film makes it clear that the Japanese soldiers were quite inventive in their methods of murder and torture.

Pic's trio of editors intercut the readings with devastating archival footage of the Japanese aerial and ground assaults, the juxtaposition of voices and images conjuring a vivid sense of life in the city as it was pillaged and burned. Yet while the actors serve to put a human face on heroism, there's a palpable, even distracting disconnect between the visual polish of these segments and the brutality of what they're describing.

More rewarding are the harrowing testimonies from Nanking survivors, including one of the few rape victims who wasn't killed immediately afterward. The film also incorporates a series of short but graphic films, made by one of the doctors, grimly detailing the wounds of the injured.

While the sleek 90-minute docu may not provide a definitive account on the order of Iris Chang's bestseller "The Rape of Nanking" (which inspired producer Ted Leonsis to make this film), the personalities it brings to light -- many of whom were forced to remain silent about what they'd seen after returning to their homelands -- are worthy of widespread exposure. The sad epilogue suggests that, 70 years after the massacre, the conversation between the Japanese and the Chinese about Nanking is just beginning.

Camera (color/B&W archival), Buddy Squires; editors, Hibah Frisina, Charlton McMillan, Michael Schweitzer; music, Philip Marshall; associate producers, Bentley, Jo Ann Jacobs; line producers, Dylan Nelson, Katie Strand, Karen Lin. Reviewed at Sundance Film Festival (competing), Jan. 20, 2007. Running time: 90 MIN.