Dead to Rights, a film set during the Nanjing Massacre, opened in domestic theaters on Friday.

Marking the 80th anniversary of the victory in the Chinese People's War of Resistance Against Japanese Aggression (1931-45), the film revisits one of the most barbaric episodes of World War II through the perspective of a group of unsung heroes.

The Nanjing Massacre occurred when Japanese troops captured Nanjing on Dec 13, 1937. Over the course of six weeks, they slaughtered around 300,000 Chinese civilians and unarmed soldiers.

Set against the Nanjing Massacre, the film follows a group of civilians sheltering in a photo studio.

Forced to develop a Japanese military photographer's film to survive, they accidentally uncover photographic proof of the atrocities. Initially focused on mere survival, they ultimately risk everything to preserve the evidence and expose the war crimes.

The movie is directed by Shen Ao and features a stellar cast, including actors Liu Haoran and Wang Chuanjun, as well as actress Gao Ye.

During the film's Beijing premiere on Thursday, director Shen said he has a special bond with reels of film as a graduate of the Beijing Film Academy, and shared that one of his most memorable assignments was to tell a story using only four developed photos.

Shen also revealed that the new movie is adapted from the same real-life story that inspired the 1987 film Massacre in Nanjing, which is about a Chinese doctor who risks his life to expose photos documenting Japanese troops slaughtering Chinese civilians to the international community.