After months of fighting over casino interests, the two major Macau gangs, the Hung Hing Gang and the Yee Ying Gang, decided to make peace. However, word spread that the leader of the Hung Hing Gang, Broken Tooth Wah, had offered a high price of 5 million to hire an outside assassin to assassinate the leader of the Yee Ying Gang, Gao Lao Zhong. In order to ensure Gao Lao Zhong's safety and prevent the world from going into chaos again, Broken Tooth Wah sent his capable subordinate, A Chen (Tony Leung), who is also a corrupt policeman, to stop it. The bald killer Yaodong (Lau Ching Wan) and the mysterious woman A Feng (Maggie Shiu) often haunt A Chen and constantly cause trouble for him. It turns out that Yaodong is a super killer sent by Mr. Hung, the boss behind the gang, to crush the Hung Hing Gang and the Yee Ying Gang. His killing methods are very sophisticated and ruthless. After some arrangements, Yaodong created a situation where Broken Tooth Wah and Gao Lao Zhong both died at the hands of A Chen, but his fate was not in his own hands.