Cheuk-Yuen and his fellow SDU members round up Tin Sun-Hei, who is shot when raising his hands in surrender to their request; after Chi-Lung receives the complaint filed by Sun-Hei, Hon-To is under orders to probe into the matter.

A Special Duties Unit known as the Flying Tigers confronts counter-terrorism, hostage rescues and other dangerous crimes.

Mute NGAR, crippled FAI, blind MANDY and deaf LUNG are sworn sisters, and they run a business to sell sporting goods. However, the business is a mere facade, and in fact, they rob the rich and give to the poor once they find out that person makes ill-gotten gains. HON-TO trains WAI-YAN, trying to help her overcome her traumatic experience, but to no avail. Noticing that everyone is talking about the vacant position of the Chief Inspector, HON-TO learns from the Commissioner that CHI-LUNG has been appointed as the new Chief Inspector. With all the SDU members being invited to attend the PHAB's Happy Day (Physically Handicapped and Able-Bodied), HON-TO re-encounters his first love NGAR in fencing competition, to his surprise, NGAR has become mute. CHEUK-YUEN and TAK-WAI help all the contestants complete their shooting training, during which TAK-WAI finds FAI irresistible and falls in love with her at first sight. In the meantime, MANDY and LUNG also leave a great impression on HOK-LAI. Once again, NGAR and the others set out for a mission. Accidentally, MANDY and LUNG are trapped when working together to open the safe, triggering the alarm of the security system and a patrol unit arrives on scene. Out of the blue, the cop vanishes without a trace...

A Special Duties Unit known as the Flying Tigers confronts counter-terrorism, hostage rescues and other dangerous crimes.

Former SDU sniper TIGER HO likes gathering information in his off time so as to help the police solve crimes in secret. HON-TO and CHI-LUNG announce that all the rookies have officially become SDU members, following which they celebrate with them. At midnight, HOK-LAI receives a text message from CHI-LAI, who makes some excuses to keep HOK-LAI there after he arrives at the shopping mall. When CHEUK-YUEN and TIGER HO have a target competition, TIGER HO is attacked and he deduces that must have something to do with his good friend, TIN SUN-HEI. Bumping into HON-TO and WAI-YAN on a street corner, CHUNG-CHAI is very delighted to see them, above which he even tells WAI-YAN about the story of HON-TO and CHEUK-YUEN's elder sister CHEUK-WAH. TIGER HO takes action to solve a drug trafficking case without knowing that SUN-HEI secretly sends someone to steal the drugs. After CIB receives intelligence in connection with firearms trafficking, WAI-YAN, through a trail of clues, uncovers that one of the boxes has already been moved away. Gangster BROTHER CAT discovers that SUN-HEI has not actually eliminated his enemies for him, and he even suspects SUN-HEI is the one who skimmed off the illegal firearms for himself. On the other hand, SUN-HEI brings a picture showing that his children were kidnapped, seeking help from TIGER HO...

CHEUK-YUEN and his fellow SDU members go to round up TIN SUN-HEI, who, out of the blue, gets shot when raising his hands in surrender to their request. After CHI-LUNG receives the complaint filed by SUN-HEI, HON-TO is under orders to probe into the matter. Off-duty MAN-KEUNG and HOK-LAI run into CHI-LAI while out on a date, and CHI-LAI even shows them the photo she took together with HOK-LAI during HOK-LAI's visit to her exhibition. Testifying for SUN-HEI's case, all of the SDU members unanimously claim that they have no idea who shot SUN-HEI after SUN-HEI surrendered. HOK-LAI and the others go to HON-TO's home to have a hot-pot meal together, and they see SUN-HEI's interview, in which SUN-HEI alleges that the SDU members took the law into their own hands. After receiving intelligence, the CIB requests to dispatch the SDU to assist their mission. Later on, they realize that there is an error in the intelligence, fortunately, CHEUK-YUEN doesn't fire any shots that could kill the innocent. With CHI-LUNG announcing to withdraw the mission, CHEUK-YUEN, who doesn't agree to WAI-YAN's investigation methods, bears the mindset that WAI-YAN must have been taking advantage of the SDU. Having given his testimony, CHEUK-YUEN goes to make a confession in the church, following which he meets up with HOK-LAI and the others in private. All of them insist to stick to their story, staying united.