Xiao shi de zi dan is a 2012 Mandarin-language Action Drama film written by Lo Chi-leung and Yeung Sin-ling. The movie is directed by Lo Chi-leung and produced by Derek Yee, Mandy Law, Zhang Zhao, Albert Lee, Shan Dongbing and Catherine Hun under the banner of Emperor Motion Pictures in collaboration with Film Unlimited and LeVision Pictures. Son Donglu, a newly promoted detective teams up with Guo Zhui, fastest gunman in Tiancheng and Xiaowu, a novice policeman to investigate the mystery deaths in a bullet factory. Xiao shi de zi dan features Nicholas Tse in the title role along with an ensemble cast including Lau Ching-wan, Yang Mi, Boran Jing, Wu Gang, Liu Kai-chi and Ching Wan Lau. The music was composed by Teddy Robin along with Tommy Wai. Cinematography was done by Chan Chi-ying and editing by Kong Chi-leung and Ron Chan. The film has a running time of 108 minutes. It was released on 11th October 2012 in Mandarin and Cantonese languages. The Film was successful at box office. Xiao shi de zi dan was made on a budget of $15 million and it was a hit at box office gross of $25 million. Distribution rights for the movie were acquired by Emperor Motion Pictures.