FAI is a talented customs inspector. His performance wins him appreciation from his supervisor. He even arrests a smuggler who has swallowed drugs. Inspector LI is in charge of Investigation Bureau. FAI replaces LI who has been hurt when he is on duty. WA becomes FAI's subordinate but WA is not acquainted with FAI's working style. FAI insists on doing the work in his own way. KONG SAl YAN is a cigarette smuggler. He managed to escape after hurting LI. He wants to leave Hong Kong. FAI leads his team to check boats leaving Hong Kong. He u s e s pepper to force YAN to surrender.

FAI and WA bring YAN to the police station where they come across CHAN KIN MAN. MAN is not polite to them and he criticizes WA as a hot-tempered man who always tortures criminals. WA is discontented. At home, WA swears to arrest the black hand as his girlfriend was killed in a case of cigarette smuggling. KONG is sentenced eighteen-month imprisonment. FAI appreciates YI who is in charge of the accusation. WA does not give up. WA's colleagues convince FAI to open the file again. TSUI KONG tricks FAI and WA. He baits them to follow him. In the water, KONG wants to kill them with his boat.

FAl and WA fall into the water. WA is saved by FAl. After the incident FAl and WA realize that they should give up their bias and FAI is accepted by his team. FAI's cousin TUNG works in the restaurant of the customs officer. His wife KUEN looks down upon him. FAI suggests that TUNG should be a customs officer. KONG tricks FAI again, Though FAI can arrest KONG, he has no way to accuse KONG. FAI brings TUNG's son KIT to a book exhibition. There he meets YI and her adopted daughter MIMI. They enjoy the gathering. FAI wants to invite YI to dine with him but YI has to go and meet her boyfriend MAN.

KONG threatens PAUL to work for him with his mother's life. PAUL has to supply cigarette to KONG. In return KONG gives him money. MAN goes to have dinner in YI's house. He gives her four film tickets. As YI's mother cannot go to the cinema, YI gives one to FAI. Knowing that Yl has broken her favourite cup, FAl buys a new one for her. However YI comes with MAN and FAI does not have the courage to give it to YI. FAI and WA gather strong evident to prove that PAUL has been helping KONG. PAU is -arrested. KONG discusses with MARTIN after PAUL has been arrested.

PAUL tells FAI and WA what he knows about KONG. KONG is arrested. PAUL hears that his mother is on the brink of death in Malaysia. MAN is instructed to escort him to meet his mother but on his way, he is killed. KONG is set free. KONG contacts LIP TAl KWAN to be his new partner. They meet in Shengzhen. However KONG is not allowed to get close to KWAN. KWAN is killed but KONG does not know. FAI finds that TUNG looks like KWAN and he persuades TUNG to impersonate KWAN. TUNG gets into KONG's car and KONG's car soon disappears. From the receiver, FAI knows that TUNG is in a dangerous situation.