The background music is called "Speechless Love".

The following is an introduction to the movie "Dark War":

"Dark War" is a police film produced by China Star Group, directed by Johnnie To, starring Andy Lau, Lau Ching Wan, Meng Jiahui and others. . The film tells the story of a policeman and a thief over the course of 72 hours. The film was released in Hong Kong on September 23, 1999, with a box office of HK$14.65 million.

"Dark War" has obvious traces of reference. The film is inspired by the film "The Negotiator" by Kevin Spacey and Samuel L. Jackson, but the story has been completely localized. . The script of "Dark War" continues the simple structure of Johnnie To's "Gunfire". Johnnie To specially invited two Frenchmen, Julien Capon and Laurent Courteaud, to join the screenplay, and his partner You Naihai served as the film's coordinator. .

The above information refers to Baidu Encyclopedia - Secret War