HONG had an ambition to be an excellent policeman as a child. His supervisor appreciates his considerable contribution and transfers him to work as a undercover. Coincidentally, he meets HEY on his last beat before his transfer. HEY has been in the police force for years and rich in experience but his recklessness makes LIN, his ex-classmate and supervisor dissatisfy. Fortunately, FAN, his best friend and partner, is their mediator. HONG almost damages HEY and FAN’S plot of arresting CRAZY BILL, a drug dealer. HONG’S brilliant performance during his training gains LIN’S recommendation to join the ANTI-CRIME SQUAD. His first assignment is to investigate the blackmailing of mini-bus drivers, which is masterminded by UNCLE THUNDER, and succeeds in having KIM, an informant, to testify. HONG is sent to protect the informant but feels quite at a loss when he meets his mother, BO, in his mission.

The exposure of HONG’S identity lets UNCLE THUNDER off the hook and leaves in rage. HONG feels regret for this. HEY knows UNCLE THUNDER collects ransoms in the name of cleaning fees and “cleans” THUNDER’S territory. This leads to LIN’S dissatisfaction. FAN has a fight with his landlady and moves to HEY’S home. HEY is dissatisfied with his career and CHI, his wife, always comforts him. His partner, TI, was a teen mother and has a son named FAI. HEY takes care of her very much and makes TI admire him secretly. HONG meets SUM when accompanying his mother to buy a used car and mistakes SUM for his puppy lover, YEE. UNLCE THUNDER’S men have penetrated in the construction site of HOME OWNER’S SCHEME to seek for interests and BULLET is in charge of this. HEY and HONG follow order to get BULLET but he resists.

HONG and HEY manages to arrest BULLET, who knows it is THUNDER’S trick that leads to his arrest later. He sends his man, PINK PANTHER, to threaten HO’S family so as to make HO quit from testifying against him and set him free. TI’S work makes her late in picking up FAI, who is missing. She is worried about her son very much. HEY consoles her and finds FAI at his home. TI’S father, WON, dislikes TI’S maternity without marriage. It turns their relationship sour. KIU, WON’S sister, works as their mediator. BULLET lets the police collect enough evidence to charge UNCLE THUNDER in order to replace him as the new boss of the gang. HONG visits SUM’S school to investigate the triad penetration of schools and tries to date SUM whom HONG mistakes her for YEE.

SUM discovers one of her student, PING involving in shoplifting and traces him but in vain as being discovered by other gangsters. Fortunately, her alertness helps her escape from mishap. Then she succeeds in persuading PING into cooperating with the SQUAD to rectify the gang of shoplifting. AT last, HONG accidentally makes clear that SUM is not her puppy lover. FAN is embarrassed when he expresses his admiration to LAI, his colleague, who only treats him as her elder friend. Coincidentally, TI cannot join KIU for concert and let FAN go with KIU. However, KIU finds FAN is such a miser that the date ends in disagreement. The SQUAD tries to hook BULLET, who blackmails the new flat owners in the name of HUNG KEE CONSTSRUCTION CO., by borrowing a flat from TI’S family. KIU makes FAN pay for a meal for this request from the SQUAD. FAN can do nothing but agree.

In order to get KIU’S cooperation; FAN pays her a meal. KIU tricks FAN to pay for all neighbors instead of hers only. It really hurts FAN, the miser. KIU carelessly discloses the plot and let BULLET off the hook. This makes the SQUAD very angry. HONG tries to engage with SUM and shows his fondness in the excuse of computer problems. Finally, he is distressed when he knows SUM has a boy friend but he still cares about her. Because of the undesirable returns from renovations, BULLET orders his gang to threaten the tenants and damage the flats of those who do not offer them the renovation works. KIU’S flat is damaged seriously because of helping the police and she requires FAN to be responsible for the renovation. For cutting costs, BULLET steals materials from other construction sites and has KEUNG, HEY’S brother-in-law joined him. They resist when the SQUAD goes after them.

HEY dislikes LIN suspecting him of shielding KEUNG and resigns in rage. FAN and TI persuades time and again in vain but his wife, CHI, strongly supports him. Although LIN stops HEY from investigating the crimes of BULLET, HEY does not obey. KEUNG falls out with HEY because he does not want to testify against BULLET. CHI is in the dilemma. HEY thinks it does not fit him for being transferred to detect the triad penetration of schools. BULLET’S men blackmail owners whose flats are finished in undesirable conditions since his business is deeply affected by the police investigation. With the owners’ cooperation, the SQUAD successfully traps and charges BULLET as well as his men. FAN and HONG are investigating a case of student stealing letters and suspect SUM’S students taking part in it. The principal obstructs them to take further action. SUM dislikes what the principal does but she can do nothing about it.

SUM finds WING taking part in stealing mail with other students and tries to stop them but they run away. The students, used by TURBO, a gang leader, play the trick of luring the principal away by putting the mail into ON’S school bag. As TURBO have students as his targets, his influence gains momentum in schools. HEY and CHI look for an ideal shop. TI envies they are great couple. CHI accidentally hears KIU mentioning TI’S secret admiration of HEY. TURBO shops with credit cards stolen by WING and his gang. When the SQUAD knows what TURBO does, it dogs and arrests WING, who shields TURBO and admits all the wrongdoing himself. WING’S grandma asks SUM for help and WING takes TURBO’S advice of pretending to be good. But the principal insists WING to quit from school.

SUM’S lofty aim in teaching is supported by HONG but not her family and boyfriend, WAH. So she and HONG ask the principal to give WING a chance. The principal agrees only if WING passes the exam. Then SUM helps WING through tutorials and WING works hard too. TURBO participates in prostitution business. A young prostitute disobeys him and accidentally hurts herself by falling on the ground from a building in her escape. This draws the SQUAD’S attention and checks all the business related to TURBO. FAN repairs water pipe in KIU’S home and takes shower. KIU mistakes FAN for TI and discloses her secrets. WING, who passes the exam and have the judge reprieved his probation, does not regret and joins TURBO’S gang again. TURBO, who persuades WING into working for him with smooth talk, is having a drug deal. The SQUAD prepares to arrest him.

WING is caught but released by the police for insufficient evidence. However, TURBO not only does not blame him but also treats him better. It is because TURBO has finished the deal and WING is just bait for the police. WING’S defying the persuasion of SUM and quitting from school let SUM down. WAH’S jealousy arises when HONG comforting SUM and going out with her for a ramble. HEY knows TURBO uses his old trick in the coming drug deal. He follows him to the bowling ground and captures them. But TURBO is bossy in the police station. When he is ready for the bailout, HEY detains him for the injury of the girl in her escape from TURBO. HONG admires HEY and HEY teaches him his secret to be a policeman. TURBO dissatisfies being teased by HEY and sends his men to destroy HEY’S new shop but accidentally catches fire while CHI is in the shop.

CHI dies of suffocation. This hurts HEY and he cannot sleep. He always reminisces their good old days. When he knows who is the murderer, he prepares to take revenge but TI stops him in time. TURBO gives YAN $300,000 for not testifying against him and YAN is sentenced for four years. SUM feels out of place with WAH. She considers separating with him but his dedication makes her continue the relationship. KEUNG rebukes HEY who gives up his business after CHI’S death. TURBO cannot return $300,000 to MARKET WAI and kidnaps ON with WING for $ 1 million at the beginning. He then blackmails another $ 5 million after ON’S father makes the first payment. ON’S father can do nothing but report to the police. At the same time, SUM, who remembers the place for hiding the hostage, tries to seek for ON with HONG.

SUM and HONG find the place for hiding ON and prepare to save him but WING stops them. At the same time, TURBO returns and threatens ON’S father to pay the ransom. HONG manages to escape and arrests TURBO. Finally, he charges TURBO with WING’S testimony. SUM thinks she is suitable to be a social worker and decides to resign. But the objection from her family and WAH puts her in dilemma. HONG’S support to SUM makes WAH angry. HEY is sullen and stays at home. TI and FAN encourages him to continue his career in the police force. In order to retain HEY’S job, FAN feuds with LIN. At last, HEY’S resumption of his work makes the SQUAD happy. MARKET WAI takes the advantage of JOE, the president of fish market, who hires him to be in charge of the security, making loans to the hawkers. His plot catches the SQUAD’S eye.

MARKET WAI becomes lawless and pushes SHING who comes to an impasse and cooperates with the police. The SQUAD then collects evidence in disguise of hawkers. FAN opens his shop opposite of KIU’S. Because of inefficiency in business running and finance by own, FAN sells a new product named EASY-SOUP-PACK and makes KIU angry. TI consoles HEI and HEI regains his enthusiasm in work. SUM neglects others’ objection and insists to be a social worker. SUM dislikes WAH, who uses her father to push her to marry him, and decides to separate with him. MARKET WAI’S threat to FAN for his blooming business leads the SQUAD to prey him. Even worse, JOE bring another wolf, PANG into the room. HONG’S father, DONG, suddenly returns to Hong Kong. When BO suggests him to put his money in term deposit, DONG equivocates because he has been extorted money by someone setting a sex-trap.

BO gets mad when she noses about DONG being blackmailed by a sex-trap. Feeling guilty, DONG decides to settle down in Hong Kong and starts his business in seafood wholesales. FAN finds it profitable and persuades KIU in having consignment with DONG. KIU, falling for FAN, certainly agrees. LIN’S wife, SHI, superstitious in fortune telling, especially believes TUNG, a con man. Annoyed by DONG’S matter, BO goes with SHI to visit TUNG. PANG’S men collect a variety of fees in the fish market which makes the public angry but JOE can do nothing about it. TI prepares a birthday party for HEY enthusiastically and everyone knows she is fond of HEY. However, HEI's declaration of their solely work relationship disappoints TI.

Since HEY’S decline of TI, TI tries to escape HEY. HONG and SUM gets together very well but JOE is still having prejudice against HONG. PANG’S men, selling cheap fish at a high price, troubles KIU and WON when they are going to sell goods in the fish market and they even beat WON. This enrages TI who goes to get them alone, but HEY arrives just in time and stops her from acting on impulse. LIN’S wife and BO, deceived by TUNG, bring a lot of money to "plant gold" but are drugged by TUNG. Fortunately, DONG follows them and tells HONG to save them. They bury the hatchet. The penetration of PANG’S power in the fish market is a menace to JOE who decides to cooperate with the SQUAD but PANG, on the contrary, controls everything and JOE can do nothing.

In order to prove KIU giving him the glad eye, FAN pretends to be sick. FAN is happy when the result is what it is. To prevent from being embarrassed with HEY, TI asks for a transfer. The team works hard to retain her but HEY encourages her to do so for having more time to take care of FAI. PANG gets worse by threatening the hawkers not to send fish to the market but to trade with him secretly. JOE can no longer take it and manages to drive PANG out of the market by cooperating with the SQUAD. He is released later due to insufficient evidence. DANG, head of the triad society at TSIM SHA TSUI EAST, succeeds in commercializing the triad society, through investment in making movies. One day, TI coincidentally meets DANG, who cheated TI years ago, and runs away from him but DANG‘S tag-on makes TI lie to him that their baby had died.

Entangled by DANG, TI is annoyed but HEY can do nothing about it. PANG’S recommendation of HACK to be the new president of the fish market makes JOE mad. PANG controls the market again and everything is worse than before. All the people are not satisfied and HONG persuades JOE to testify against PANG. After this, JOE expresses his kindness to HONG and no longer objects the engagement between him and Sum. Knowing KIU’S serious concern about him, FAN is proud of it but does not want to marry her. Fearing marriage, he pretends having a hereditary disease and keeps away from her. However, KIU’S generosity touches FAN. Besides, FAN being a male chauvinist enrages KIU.

In order to escape DANG’S entangle, TI tells DANG HEY is FAI’S father but DANG believes in doubt. DANG opens a seafood restaurant. To avoid being blackmailed by triad society DANG has KEI as well as MUI jointly managed the restaurant and triggers the hatred between them. At last nobody wins but DANG. Dissatisfied with FAN, KIU aims at upsetting him by admiring SHING wholeheartedly and going to SHING’S birthday party. FAN’S serious chase after KIU makes her agree to marry SHING rashly. HONG throws himself in his work, neglecting his concern on SUM. This irritated SUM. YEE adding fuels to the flame, SUM suspects HONG’S affection to her. Proving FAI as his son through DNA test, DANG is mad at the intimacy of the trio--FAI, TI and HEY.

KIU hurries to the police station and tells TI that FAI is missing. In fact, FAI is picked up by DANG, who tries to get close with FAI by going with him for a ramble and satisfying his needs. Enraged, TI unexpectedly beats FAI. AT the same time, DANG sends TI a legal letter to claim for FAI’S custody. Getting rid of KEI and MUI, SPICY CHICKEN targets KUK and sends somebody to assassinate him. Fortunately, KEUNG, who follows him later, saves KUK. Knowing KEUNG giving up himself HEY dares to challenge SPICY CHICKEN for the sake of his wife so as to force KEUNG mending his way. Worried by HONG’S neglect to her, SUM hesitates whether to study in U.K. However, HONG, busy at the preparation for exam, encourages her to study abroad.

To strive for FAI’S custody with DANG makes TI sullen for several days running. On the other hand, DANG not only tries to win a good impression from FAI, but bribes MRS LI, the nanny, to testify against TI. Fortunately, HEY’S evidence, proving DANG’S imprisonment in TAIWAN, forces DANG to give up scrambling for the custody of FAI. Being embarrassed, KIU lets FAN explain to SHING. Via female seduction, FAN makes SHING give up the marriage. YEE hints at HONG so HONG starts to care for SUM with dedication. DANG becomes influential and manages his illegal activities, including international peripheral gambling houses. KEUNG is not appreciative of HEY who tries every means to persuade him to turn a new leaf and he picks on HEY. HEY cannot help it.

DANG focuses on expanding his horse- racing gambling group. SPICY CHICHEN and KEUNG work hard to build up their clientele base and the result is good. This activity leads to the SQUAD’S lightning attack to arrest them but releases them for insufficient evidence. The rumor of SHING abandoning KIU, who is pregnant, makes WON turn the tables- forcing KIU and FAN to get married. FAN agrees but worries about the wedding banquet. KIU asks FAN to buy her a diamond ring but FAN has bought a faked one. The demand for SHING’S repayments of debt by loan sharks discloses that the ring is faked which makes KIU angry. In order to get FAI, DANG sends KEUNG to kidnap him. Coincidentally, KEUNG meets HEY who chases after him. This leads to a car accident.

TI, enraged for FAI is in coma after the car accident, shoots DANG and is suspended for work. DANG ‘S horseracing gambling group is influential and colludes with other active in the horse racing. In his pursuit, HONG meets WAH and invites him to cooperate with the police but is taunted by him. WAH decides to help the police testifies against DANG when he is beaten up by SPICY CHICKEN for not repaying his debts. The SQUAD cooperates with the police force in Mainland China, manages to arrest DANG and gets the useful evidence-- compact discs. SUM goes to U.K. for studying unwillingly but HONG, being busy, does not go to the airport. TI asks DANG to do her a favor because DANG’S blood is the only choice for the success of FAI’S operation. DANG takes this advantage to run away with TI as well as a female patient as his hostages.

Kidnapped TI & the female patient, DANG wants to have the discs back, even threatening HEY with TI’s life. To save TI, HEY unexpectedly steals the discs from the evidence room. FAN, however, discovers and stops HEY, who beats him unconscious. The aim of their squabble is to trap “DANG who is successfully send to jail at last. When TI visits him, DANG’s incorrigible attitude lets her down. Fortunately, HEY consoles her and they plan to get married. In order to save money, FAN persuades HEY and GRASSHOPPER to have a collective wedding ceremony. After finishing her work, HONG goes to London to visit sun, he has left without knowing HONG’s trip to London. Returning to HONG KONG, HONG is disappointed for not seeing her. In the end, how did it turn out between the two?