Sun Ma Chai witnesses, a robbery while he is taking his driving test for traffic warden. He helps Siu Fei Hop to catch the robber.

As Sun Ma Chai passed the test, he is sent to Kowloon Headquarters and he is assigned to work in Sir Choi’s unit. Siu Fei Hop, Tai Sze Hing, Chu Chai Chain and gan Ken Thai are his colleagues.

Sun Ma Chai carries out patrol with Ngan Ken Shai. In order to get promotion, Ngan Ken Shai sends out tickets relentlessly and he pays no attention to the actual situation. When he is charging Cheung Kam Fai, he quarrels with Tze Wai. Sun Ma Chai acts as the mediator and personally, he does not appreciate Ngan Ken Shai's attitude.

Tze Wai criticizes Ngan Ken Shai's misbehavior in the newspaper. Ngan Ken Shai is blamed by Sir Choi. Ngan Ken Shai is displeased as Sun Ma Chai has refused to speak for him.

While Kam Fai is on the way to pick Tze Wai up, he is robbed by a strange man……