An undercover cop sent to infiltrate a notorious crime ring, Ko Chow (Chow Yun-Fat) must replace a fellow officer who was killed in a violent confrontation. But, as he earns the trust of the syndicate, he develops a tight friendship with one of the thieves. Then, when a planned heist turns into bloody shoot-out with police, suspicions arise about who could be the informant! As friendship and loyalty clash with duty and honor, you'll be riveted by the explosive power of this intensely entertaining motion picture.