BEIJING, March. 1 (Xinhua) -- The Golden Bear winning Chinese movie "Black Coal, Thin Ice" will hit domestic cinema screens on March 21, the film's director Diao Yinan said in an interview with Xinhua.

The thriller, which is about a washed-up former cop investigating a series of murders, won the Golden Bear, the top prize awarded to the best film at the 64th Berlin International Film Festival on Feb. 16.

Chinese actor Liao Fan, who played the detective, won the Silver Bear for Best Actor.

Diao said the film intends to "demonstrate people's courage to make moral choices when facing the truth, and to help today's Chinese be less tense."

"There is a dark side inside everyone," Diao said. "It may be an impulse, a state of madness, and it may erupt regardless of moral bounds."

"Black Coal, Thin Ice" is the fourth movie from the Chinese mainland to win the Golden Bear after Xie Fei's "Women from the Lake of Scented Souls" in 1993, Zhang Yimou's "Red Sorghum" in 1988, and "Tuya's Marriage", directed by Wang Quan'an, in 2007.