Trainee Inspector Yuan Hui is well-known in government departments and the underworld. He is friendly and unconventional. He is on good terms with his subordinates Yeh Chiu and Shih Kou-kung and often appeases them, winning their respect. Lin Hsi-wei, returned from overseas, becomes Yuan Hui's superior. A stickler for forms who exercises strict control over Yuan's subordinates, she often quarrels with Yuan. Shih Kou-kung reaching retirement age, applies for extension, but Hsi-wei turns it down due to dissatisfaction with his working attitude and plans to have a new man Ma Jo Chi replace him, thus earning their hostility. On the wedding day of Yen Chiu, his girlfriend Yuan Chiu-yen, resenting his change of heart, kills herself in public, causing him much embarrassment. Subsequently, they discover a videotape recorded by Yuan alleging vengeance on him even at death……

Yuan Hui's cohabiting girlfriend, Pao lien, who arranged the marriage for the Yeh Chiu couple and who witnessed Yuan's suicide, feels fittery day and night, fearing that her spirit may haunt her. Li- hung, who has been at variance with her, plays a ghost to scare her. Wen Yung, who was extremely nice to his late sister Chiu-yen, took it for granted that Yeh Chiu and his company were responsible for her death, and determines to kill anyone concerned with arranging the marriage. An ex-Vietnamese refugee, who received military training before arriving at Hong Kong, Wen Yung had a fierce disposition. Disguised as his deceased sister, he drives at night to Pao Wen's home to scare her, throwing her off the balance. When told of this, Yuan Hui suspects. When escorting illegal immigrants, Shih Kou-kung and others gamble on the police van, resulting in their escape. Hsi-ya tries to knock the truth out of them, but in vain……

Killing Shih, Wen-yung, disguising as Chiu-yen, sneaks into Pao-wen's house and intends to suffocate her in the bathroom. Hui arrives on time to save her and feels suspicious. With a Vietnamese knife found in Pao-wen's house, Chiu suspects that both murders are done by Wen-yung and swears to arrest him. Li-hung brings her alcoholic father to the bar where she colludes with the waiters to cheat him out of money. Discontented, Hui argues with the waiters and scold Li-hung once discovering her fraud. Finding out that Wen-yung is acquainted with some guys of a health club, Hui sends Chi to join them in order to know Wen-yung's where- abouts. His identity being exposed, Chi seeks help from Hui and in confusion, hurts Li-hung. Seeing Wen-yung running away, Hui forces the guys of the health club to speak out where he is. Hui arrests him with Chiu who is confines in Yung's house.

Sorry for hurting Li-hung, Chi visits her in the hospital with Hui. Before the ignorant Chi, Li-hung intends to win his sympathy by posing to be poor. Though quick-witted, An refuses to pursue and ordinary job but guards the gambling dens. Because of his conflict with Chiu, An is believed to be serving the police and becomes unacceptable to both the underworld and the police. Thinking that he is, afterall, his relative, Hui finds An, who seeks his help, a job in a private detaective agency. Hui is drunk during his birthday party at home. Returning from the hospital, Pao-wen quarrels with Hui when she finds the house in a mess. Though separated, Hsi-ya's husband Tzu-chi, hoping to reconcile in order to inherit the family's fortune, bothers her persistently, much to the disgust of Hsi-ya. Despite his dispute with Hsi-ya in work, Hui helps her to repel him by pretending to be her lover.

Hui saves Tze-chi who is threatened by a robber with a bomb. Tzu- chi Complains Hui for forsaking his life in order to arrest the robber but is embarrassed knowing that Hsi-ya is the superior. Failing in her study, Li-hung wanders around with the gang. To get money, she even asks her father to give her the medical fee lying that her foot is still painful. Chi's care for her displeases her. Tzu-chi keeps picking at Hui and finds excuses to approach Hsi-ya. The circumstances help Hui and Hsi-ya to reconcile and the two fall in love. To revenge Tzu-Chi's insult on Hui, the greedy An Steals Tzu-chi's purse which contains a large sum of money. Resenting their intimacy, Pao-wen scolds Hui misunderstanding that he and Hsi-ya have an affair.

Tzu-chi's purse is taken away by An's debtor who discovers in it a document convening the delivery of precious jewellery and conspires to rob it. Knowing the plot from An, Hui rushes to the spot and is shot by the robbers, much to Hsi-ya's worry. Scolded by Chi for lying that her foot is hurting her, Li-hung, indignant and sad, admits her sorrowful experience which arouses Chi's sympathy. Despite Hui's explanation, Pao-wen, worrying that Hui and Hsi-ya will ultimately fall in love, hints to Hsi-ya that as her intimate classmate, she should retreat from the eternal triangle. Frustrated in love affair, Hsi-ya drinks with Hui. Discovering that they are still close to each other, Pao-wen leaves Hui.

Though deeply impressed by Hui who helps her at the expense of his reputation. Hsi-ya declines his courtship owing to her friendship with Pao-wen. Hsi-ya and Hui become intimate once Pao-wen leaves him. Chi's kindness and concern arouses Li-hung's love for him. But her rudeness displeases Chi's mother when they happen to meet each other. Chi saves a broker Ting when he discovers that a sex maniac is trying to molest her in an empty apartment which Chi and his mother want to inspect. Though delighted at Hui's courtship,. Hsi-ya, warned by failure in her marriage, hesitates to accept his lvoe. Chi's mother encourages the shy Chi to court Ting and arranges meetings for them.

Annoyed at finding Chi and Ting together, Li-hung lies that she is Chi's wife, much to Chi's anger. To test Chi's affection for her, Li-hung flirts with the patrons of the brothel. Scolded by Chi and knowing that she is treated only as his sister, Li-hung drowns her disappointment by drinking. Sad at Li-hung's parasitic life, Hui intends to send her abroad to study. Understanding that she is not good at studying and impressed by Hui's encouragement, Li-hung decides to operate car renting business. Soon After the business starts, Li-hung's car is damaged by her client. To make up for the loss, she and An bump their car into other vehicles on purpose and then blackmail the drivers.

Chi frisks a juvenile deliquent Hsiung who clashes with others when boarding a van. Sympathizing Hsiung, Ting quarrels with Chi due to his fierce manner. Li-hung's high income arouses Hui's suspeicion. Knowing from An that they live on trickery, Hui searches for Li-hung. A female drive, blackmailed by Li-hung, fights back and gets hurt. Hui promises his sister to hide the crime and provides false testimony to the police. Suspicious, Hsi-ya finds out that the injured's car is rent from Li- hung and An and orders the investigation of Li-hung. Li-hung's admittance of her fault involves Hui who is likely to be dismissed.

For the sake of Li-hung's future, Hui hides the fact and recruits a first-rate lawyer to protect her. Understanding that his betrayal of the law will not be tolerated by the police force, Hui resigns. Ting asks Chi to punish Ling who, on probation, earns a living as a prostitute. Indignant, Ling kills herself by drinking detergent and is sent to the hospital. Leaving Hui, Pao-wen drowns her sadness by gambling. She tries to attract Leader Hua of the gang and later becomes his mistress. Ting is appointed to guide Li-hung who, regarding Ting as opponent, refuses her. Helped by Ting when she is bullied by a gang, Li-hung and Ting become friends.

Because of his limited qualification, the jobless Hui fails to find a satisfactory job and drinks day and night, Hsi-ya encourages him to start again. Meeting Hui, Pao-wen, still loving him, suggests they operate a tourist agent hoping to regain his affection. Due to their contacts in work, Hui becomes close to Pao-wen and seldom meets Hsi-ya who nevertheless understands Hui's situation without blaiming him. One day, as the busy Hui fails to show up at their appointment, Pao-wen walks around alone and runs into a sex maniac. Pao-wen being saved by Hui, they become more intimate. After becoming Leader Hua's mistress, Pao-wen discovers his viciousness and his intention to control her by money. Deeply hurt, she expresses her sorrow before Hui who sympathizes her. The marriage between Hui and Hsi-ya arouses the hatred of Pao-wen who decides to ruin the business of the tourist agent. Hui argues with her but is jeered at……

Knowing that Hui is persecuted by Pao-wen, Li-hung and her friends damage her car. Pao-wen charges Li-hung but is teased by Chiu. Worrying that Hui, failing in his business, will not be able to return him his savings, Ping falls ill. Frustrated in work and urged by Ping to return the debts, Hui feels hopeless. Hsi-ya begs Pao-wen to change her mind but Pao-wen decides to break all relations with her and Hui. Li-hung uncovers Pao-wen's wicked act before the crowd when Leader Hua and Pao-wen are in the disco. To save face, Leader Hua says nothing. Later, he presses Pao-wen to tell the truth and is furious to know that the large amount of money given to her is indeed used to help his ex-lover in business. Hating Hui who, as an inspector, has repeatedly offended him, Leader Hua, now his creditor, insults him by forcing him to eat sour food.

Since discovering her love for Hui, Leader Huh abuses Pao-wen who determines to leave him and in revenge uncovers his illegal acts to Hui, requesting him to report to the police. Worrying that Hui will not be able to return him the savings, Ping becomes worse. Ashamed, Hui decides to get monty by all means. With nobody to turn to,. Hui conspires to rob a jewellery shop with An and sends him to rent guns. Hsi-ya perchance discovers that Hui has brough weapons but he denies, Hsi-ya's search of his house, though fails, alerts Hui. To prove that he is not in the spot during the robbery, Hui asks An to dress up like him and drive around on a motorcycle, causing trouble as well as arousing public attention. After robbing the shop, Hui exchanges his bag with An who will hide the jewellery while Hui continues driving on a motorcycle publicly.

Unexpectedly, An kills a passer-by in a car accident. Charged by the eye-witnesses, Hui bears the brunt and gets jailed for half a year. Without Hui's consent, An uses the money to operate a Hi-fi shop and shows off his richness which arouses Chiu and the others' suspicion. In jail, annoyed at An's complete seizure of the jewellery, Hui unravels the truth to Li-hung, sending her to blackmail An at the opening ceremony of his shop but An refuses her demand. Knowing that Tzu-chi will soon die of disease, Hsi-ya comforts him hoping that he will enjoy his limited life time. Misunderstanding that the love between Hsi-ya and Tzu-chi is rekindled while Hui is in jail, Li-hung plays tricks on him and feels guilty knowing that he is dying.

Failing to get money from An, Li-hung insists him to settle the matter with Hui. An promises Hui to give Li-hung his. share but later ignores her. To revenge,. Li-hung uncovers to the police that An, a Hi-fi shop owner outwardly, is indeed making loans illegally. Well-prepared, An has a drug-addict to bear the brunt. Annoyed at Li-hung's repeated trickery, An sends a raseal to threaten her but accidentally, he is beaten to death by Li-hung and her friends. While removing the corpse in a paper box., Li-hung perchance comes across Chiu who helps her to take the box home. Her crime being discovered by Kang, Li-hung escapes. Hearing of Li-hung's offence, Hui wants to phone his family but owing to the rigid regulations, his request is turned down.

Chased after by the police, Li-hung and her friends split. Knowing where she is, Hsi-ya orders the arrest of Li-hung regardless of their intimacy. After a long stalemate with the police, Li-hung is killed falling down from the building accidentally. Released, Hui discovers that An is responsible for Li-hung's death but An's denial troubles him. Hui loses the incentive to work and becomes cold to Hsi-ya, concertrating on collecting evidence to prove An guilty. Informed that An, after failing in his illegal loan business, deals in narcotic, Hsi-ya sends the police to search his house but is shocked to find it empty.

Moved by Hsi-ya, Hui decides to start again afd gets married immediately. On the day of his marriage, Hui is saved by a policeman when attacked by An's follower. Their antagonism enhanced, Hui secretly joins An's gang and captures An. Scared, An agrees to return Hui his money. Understanding that Hui intends to take vengeance on An, Hui-ya persuades him to give up. Failing to Thailand for their honeymoon, not knowing that Hui has made plans to trap An. To put an end to his worry, An sends his follower to kill Hui during his honeymoon but fails. Suspicious, Hui returns to Hong Kong to find out the truth.

Returning to Hong Kong alone, Hui challenges An by disguising as policeman and confiscating both the narcotic and the money. Losing all his fartune, An breaks into Hui's house with a gun and threatens to kill Hsi-ya unless Hui surrenders all the money. Refused, An to kes Hsi-ya hostage. Chi persuades Hui to surrender An's fortune for Hsi-ya's sake but is refused. Blaming himeself for involving Hsi-ya in his conflict with An, Hui hestiates to take action. How will Hui handle the problem? Will Hsi-ya be killed? Will An be able to escape? So, don't miss the ending of Operation Sharkhunt.