Relentless in its graphic depiction of the pre-World War II "Rape of Nanking" in which an invading Japanese military slaughtered over 200,000 Chinese citizens and raped tens of thousands women, girls and, on occasion, even boys.

While the Crystal Heart Award-winning film is undoubtedly one of the most intense films to play the 2007 Heartland Film Festival, Oscar-winning documentarians Bill Guttentag and Dan Sturman ("Twin Towers") have created a film that transcends even its obvious anti-war message with the powerful true story of a young of Westerners who stay inside the city during the siege and end up saving the lives of 250,000 Chinese.

Sturman and Guttentag take the unique approach of using known actors such as Mariel Hemingway, Rosalind Chao, Woody Harrelson and Jurgen Prochnow to read aloud the diaries, letters and personalized accounts of daily life in Nanking during the invasion. This approach, coupled with an abundance of footage snuck out by the Westerners once they eventually left Nanking, creates one of the most powerful war documentaries ever caught on film.

The real-life Westerners, there were 22 in all, created a makeshift Safety Zone that was never officially recognized by the Japanese military and, yet, the hospital, college and other buildings in the Safety Zone became a safe harbor for thousands of Chinese after the invasion began in December 1937.

Along with the actors portraying roles, the filmmaker's wisely include a variety of first-person accounts from "The Rape of Nanking," including testimonies from both survivors and perpetrators of the acts. To this day, many Japanese deny the reality of "The Rape of Nanking," stating that it is not within Japanese culture for such acts to have been perpetrated. The abundance of evidence, testimony and video brought to life in "Nanking" would undoubtedly prove otherwise.

While "Nanking" is undoubtedly one of the most effective documentaries in capturing the truly evil side of war, it falters on a certain level with its noticeable absence of humanity despite, at its very core, being about the 22 men and women from several countries who risked their lives to save thousands. It is nearly impossible to be inspired by their courage when we are repeatedly faced with relentlessly graphic accounts, photographs and videos that remind us of the horrific deeds that still took place despite the courage of the Westerners.