Witness Insecurity

Inspector HUI WAI-SUM of the Witness Protection Unit(WPU) and his squad have accomplished the task of protecting a key witness in a drug trafficking trial, which is highly praised by his superior LAU CHAM-KWAN. WAI-SUM goes home to rest, while his fellow colleagues - CHAN KAR-SHI, YEUNG YIU-TUNG, CHEUNG LAI-KUEN and others seize the opportunity for cakes and ale. Later on, WAI-SUM pays a visit to his aunt CHAN YUK-LAN in her fruit store, and she invites him over for dinner. However he is so exhausted that he oversleeps. Upon arrival, he realizes that YUK-LAN and her family have postponed their dinner time just for him. Just then, his cousin, LI HAU-YAN, coaxes him into buying her a tablet computer. Offhand he agrees. Tycoon KIU KONG-HO hangs out with chums for a drink. Out of the blue, a hidden shooter fires upon him, creating a furor among the city. Knowing that his younger brother gets ambushed, KIU KONG-SHAN leaves from work instantly rushing back to Hong Kong. WPU is assigned to protect KONG-HO. WAI-SUM and his squad are summoned to station in KIU's mansion, arousing dissatisfaction among KONG-SHAN's wife CHOU MEI-HUNG and others. In an attempt to mediate the dispute in private, KONG-SHAN instructs his assistant, HO SIU-LEUNG to fish out the information of KONG-HO's foe. Upon investigation, the Crime Unit deduces that it is a cross-border crime and the assassin is from Shenyang. Suspecting that KONG-HO gets involved in an illegal business of the Shenyang Group, they decide to dig up the truth from it. Meanwhile, KIU CHI-LAM, KONG-SHAN's daughter, dashes back home from Taiwan the minute she learns about the attack. She appears so arrogant and aloof that members of WPU find her very intolerable.

Quite the opposite, CHI-LAM shows her father a delighted smile upon their returning to her room. For fear CHI-LAM will be disturbed, KONG-SHAN forbids WAI-SUM and his squad from going up to the second floor, which leaves KAR-SHI and YIU-TUNG an unfavorable impression. YIU-TUNG goes to a dinner with WAI-SUM at YUK-LAM's home, during which he is dazzled by HAU-YAN's trendy style. WAI-SUM bumps into a group of construction workers on his way home, triggering a flashback to his childhood. Although he was rescued from a fire by his neighbor - a construction worker, he lost his parents in that fire. Having found out that KONG-HO is in fact targeted by HUNG FEI, a really powerful man in Shenyang, KONG-SHAN asks a favor from an intermediary Director CHOU to negotiate with HUNG FEI. CHUN-KAI proposes to KONG-HO that he is planning to run a casino with pals in Malaysia, yet is blown off. In the shopping mall, CHI-LAM manages to get rid of her bodyguards and sneak out to enjoy herself listening to music at backstairs. To her surprise, a killer turns up and takes her hostage.

Assistant Commissioner of Police Bao Sir meets up with KONG-SHAN at KIU's home, during which he implies that the police have surmised his secret reconciliation with HUNG FEI. Though smiling, KONG-SHAN utters not a word. HUNG FEI comes to Hong Kong to meet KONG-SHAN, and have a pleasant chat with the KIU brothers. KONG-HO gets stinky drunk so that HUNG FEI offers to give him a lift. However he speaks out of turn infuriating HUNG FEI. All of a sudden, HUNG FEI pulls out a pistol and fires on him. By accident, a foreigner is shot to death by a stray bullet. The whole scene has been caught up by CHI-LAM. HUNG FEI is taken under custody by Patrol Sub Unit (PSU). KONG SHAN dashes for the hospital to visit his brother knowing that a disaster is imminent, as it turns out that the victim is actually a retired judge. HUNG FEI's driver pleads guilty, which differs from CHI-LAM's testimony. In order to revoke her testimony, HUNG YEE, HUNG FEI's younger brother, calls on KONG-SHAN and pressures him into persuasion.

During ID Parade, CHI-LAM bursts out screaming and flees from the room as soon as she sees HUNG FEI. SIU-LEUNG reports to KONG-SHAN, indicating that HUNG YEE has sent his henchmen to wreak havoc on his subsidiary companies in Shanghai and Chongqing. Misconstruing that CHI-LAM is in trouble, WAI-SUM breaks into her room, which scares her to death. Boiling with rage, KONG-SHAN gives WAI-SUM a severe telling-off. WAI-SUM is called back to the police station by CHAM-KWAN the next day. It turns out that KONG-SHAN offers to disclose CHI-LAM's secrets to him. A fire breaks out when CHI-LAM is practicing in the Sinfonietta. After escorting her from the fire scene, WAI-SUM nonetheless rushes back to the blaze retrieving her cello in the nick of time. In fact, some assassins sneak into the fire scene. Assuming that he has got rid of them, WAI-SUM, however, runs into another group of assassins. Desperate to find out ways to deal with HUNG YEE, KONG-SHAN calls BONG and other close friends in for a discussion. CHUN-KAI tries to please him, but in vain. Having regained consciousness, KONG-HO is discharged from hospital returning home. Despite him seeming vigorousness, he suffers from a sequela, torturing him in the still of the night.

Outpouring the agony of anxiety in a morning storm with gusty winds, CHI-LAM plays the cello so loud that annoys MEI-HUNG, who is feeling unwell. In the eyes of KA-SI, LAI-KUEN and others, this has crossed the line. KONG-HO reveals to WAI-SUM the cause of CHI-LAM's illness in hopes of clearing up the misunderstanding. Endeavoring to prove his worthiness to KONG-SHAN, CHUN-KAI boldly follows a gangster YUEN-KWAN back to the mainland to negotiate with HUNG YEE, but ends up being seized and maltreated. SIU-LEUNG goes to his rescue. Noticing that HUNG YEE is captured, HUNG YUNG, the youngest of HUNG brothers, has to disguise his anger cooperating with KONG-SHAN. YIU-TUNG promises to buy HAU-YAN a new telescope as gift trying to win her affections. CHI-LAM drops in at her former residence in Shek O, where she gets help from WAI-SUM in setting up an astronomical telescope for stargazing at night. Recalling her childhood spent with her brother, she gets a sense of D_j_ vu just as this.

A theft has reportedly taken place in the house and sixty thousand dollars in cash has vanished. MEI-HUNG points the finger at WAI-SUM's teammates, but she is requested not to pursue it further by KONG-SHAN in hopes of burying the hatchets. Nevertheless, WAI-SUM is resolved to look into the matter on his own. With CHI-LAM's assistance, he manages to prove that the members of WPU are in the clear. To show his gratitude for her, he gives her a cactus as gift. Having learnt from the Manager of the Sinfonietta that the world-class pianist Hack Martin would like to collaborate with them for exchange performances, CHI-LAM is thrilled and eager to give a try. That meets with fierce opposition from WAI-SUM, but he finally gives in and assents to her request. CHI-LAM returns to her former residence for rehearsal, during which her favorite scarf blows away. For fetching her scarf, WAI-SUM climbs down the hill, whereupon he finds human remains.