Hong Kong director Tsui Hark's "The Taking of Tiger Mountain," based on a real-life Communist undercover agent, will hit cinemas on the Chinese mainland on Dec. 24.

Based on "Tracks in the Snowy Forest," a popular novel by Chinese author Qu Bo, the film centers on Yang Zirong, a Communist soldier who went undercover among mountain bandits in the snow-covered forests of northeast China in the 1940s. Yang successfully blended in and helped his comrades take the mountain.

At a Monday press conference, Tsui said his interest in making the film dates back to the 1970s when he watched a Peking opera adapted from the novel.

"After watching it, I made the resolution that, if I ever got to make a film about the mainland, I'd shoot this story," he said.

According to Tsui, the film is an homage to heroes. "Many heroes, known or unknown to us, exist in history, and their sacrifices should not be forgotten."

The movie, which is produced by Bona Film Group, stars Zhang Hanyu and Tony Leung Ka-fai. It will be released in 3D.