Wu Sir had a talk with Pak Kiu to persuade him to reconsider his decision to resign. Hau Ko and Chung saw them coming out from the shooting range. Hau Ko assigns Chung to follow Pak Kiu while he follows Wu Sir. Wu Sir leads Hau Ko into a dead end.
Wu Sir warns Hau Ko that he will be punished for his crimes. Wu Sir says the whole police force is working hard to arrest Hau Ko. Hau Ko brushed off Wu Sir's comments and calls him naive. Hau Ko says the most the police can do is to place more undercovers in Chun Hing. He tells Wu Sir that he knows there are two undercovers in Chun Hing, but one is already dead. Wu Sir is confident that Hau Ko does not know who the other undercover is. Wu Sir says if Hau Ko knew, he would already finished off that person.
Chung follows Pak Kiu and sees that he is meeting up with Sam Jie. Sam Jie calls Pak Kiu out to offer prayers to Laughin as that is the last seventh day of his death. Sam Jie says she will prepare a plague for Laughin and asks Pak Kiu to offer prayers on her behalf in case she is not around.
Chung reports Pak Kiu and Sam Jie's meeting to Hau Ko. Hau Ko begins to suspect Sam Jie and asks Chung his perception of her. Chung says Sam Jie is a nice person all round but she cannot be taken lightly as she has managed to say with Tin Ko for so many years. Hau Ko tells Chung about the secret listening device found in Sam Jie's necklace. Hau Ko also tells Chung that there may be another undercover cop in Chun Hing.
Yau Yau calls Lap Man to meet her at a restaurant. Upon reaching the restaurant, Lap Man sees someone with Yau Yau. Yau Yau has arranged for a lawyer to officiate their wedding. When Lap Man finds out what Yau Yau has planned, he disagrees to continue with it. Yau Yau is upset that Lap Man refuses to proceed with the ceremony and storms off.
Lap Man chases after Yau Yau and tries to explain. He admits that he is not ready to marry Yau Yau. Yau Yau asks him if he plans to ever marry her. She tell Lap Man that she already knows his real identity (undercover cop). Lap Man asks Yau Yau why she wants to marry him if she already found out who he is. Yau Yau says she's doing that to protect him from Hau Ko. Yau Yau accuses Lap Man of cheating her emotions just to get close to Hau Ko but Lap Man denies. He says he is true to Yau Yau since the first day they met. All his feelings for her is true.
Lap Man tells Wu Sir that his indentity may have been exposed. Wu Sir is very concerned and orders Lap Man to remain in the safe house for the time being. Lap Man refuse as he is determined to capture Hau Ko. Wu Sir disagrees as Lap Man will be risking his life. Wu Sir finally agrees to continue with the program but tells Lap Man to stay in the safe house for a period of time until the situation is safe for him to return to Hau Ko's side.
Yau Yau tries to contact Lap Man but failed. She cries to Sam Jie and tells Sam Jie that she had a confrontation with Lap Man. She also tells Sam Jie that she could not locate Lap Man. She is worried that Lap Man is plotting on how to bring Hau Ko down. Sam Jie says Yau Yau should feel it in her heart whether Lap Man is true to her or only using her. She knows Yau Yau is genuinely worried for Lap Man too. Sam Jie assures Yau Yau she will think of a plan to solve this problem.
Sam Jie prepares dessert for Hau Ko. She asks Hau Ko if he ever thought of leaving Chun Hing. Sam Jie shares with Hau Ko her fears of him "disappearing", just like Laughin and Tin Ko. Hau Ko says it's not easy to just "let go". Sam Jie suggests to Hau Ko to migrate to another country. She says she could not afford to lose Hau Ko as he is the most important person in her life. Hau Ko agrees to Sam Jie's request.
Yuk Bo tells Pak Kiu a case that she encountered while on duty. She met a fellow policewoman who was inspired by another policeman. That policeman she was talking about is actually Pak Kiu. Pak Kiu remembers the incident well and reflects on the reasons he became a police officer. The next morning, Yuk Bo goes for her usual morning jog. To her surprise, Pak Kiu joins her.
Sam Jie and Hau Ko tells Fa Si Lai their intention to get married. Sam Jie says she doesn't plan to have a banquet dinner. Yuk Bo and Pak Kiu came home and was displeased to see Hau Ko in their house. Yuk Bo opposes Sam Jie's marriage to Hau Ko. Sam Jie explains that she and Hau Ko will have their wedding on a cruise and then migrate to another country. Hau Ko will also leave Chun Hing and not meddle in Chun Hing's business after their wedding.
Sam Jie shares the news of her impending marriage with Yau Yau. Yau Yau was delighted and together with Sam Jie cooked a lavish dinner for Hau Ko. Hau Ko asked Yau Yau about Lap Man. Yau Yau lies to Hau Ko and says Lap man has to visit his sick mother overseas. Chung drops by during dinner and congratulates Sam Jie and Hau Ko.
Hau Ko bring Sam Jie to a remote place. He tells Sam Jie that he has been hiding something from her. Hau Ko promises to be truthful to Sam Jie from that point onwards as they will be husband and wife soon. Hau Ko confessed that he was the one who planned Tin Ko's death. He was the one who tipped off the police. He also planned Tin Ko's abduction during police transport. Sam Jie was shocked to hear Hau Ko's confession. Hau Ko tells her that he purposely attacked Chung to gain her trust and support to be the leader of Chun Hing. Hau Ko gave Sam Jie the gun and asked her to shoot him to revenge for Tin Ko.
Sam Jie is unable to point the gun at Hau Ko and instead dropped it. She walks away from Hau Ko and went to visit Tin Ko at the columbarium. She apologised to Tin Ko as she has sided and fallen in love with the "enemy".
Sam Jie goes home and was greeted by Fa Si Lai and Yuk Bo. They each gave Sam Jie jewellery as her wedding gift. Seeing both her mother and sister so happy, Sam Jie does not have the heart to inform them about the latest developments with Hau Ko. Fa Si Lai lament that she will once again miss Sam Jie's wedding as Sam Jie and Hau Ko will have their wedding on a cruise. Fa Si Lai tells Sam Jie to take good care of herself.
Sam Jie receives a call from her staff telling her there's a stench coming from the kitchen. Sam Jie says she will check on it. She found a dead rat in the kitchen. But she also discovered the hidden door to the concealed kitchen where drugs are produced.
Sam Jie was stunned by her discovery. She quickly called Fa Si Lai and tells her not to return to Oi Sam Ook from the next day onwards. She then called Pak Kiu out to clarify some matters with him. She asked Pak Kiu questions hypothetically - if she was not aware of what was happening in her kitchen, will she be implicated too as the owner of the place? Pak Kiu was worried and sense that something is wrong.
It appears Chung was the one who intentionally let Sam Jie "discover" the drug factory. He did it without discussing with Hau Ko because he wants to test Sam Jie's loyalty. Chung tells Hau Ko that after Sam Jie discovered the factory, the first thing she did was to look for Pak Kiu. This "clearly" shows where her loyalty lies. Chung says if Sam Jie choose to betray Hau Ko, she will call Hau Ko to Oi Sam Ook and tip off the police.
Sam Jie calls Hau Ko to Oi Sam Ook, but did not tip off the police. However, Hau Ko doesn't know that and thinks she has betrayed him. He goes to Oi Sam Ook fully prepared with a loaded gun. Sam Jie cooked some stuff for Hau Ko to eat. While eating, Hau Ko and Sam Jie talked about the first time they met till what the events that happened recently. Pak Kiu sends Sam Jie an SMS telling her to reveal what Hau Ko had done, but Sam Jie replies, saying she chooses to believe that Hau Ko had really loved her.
Hau Ko brings Sam Jie into the factory. He tasted the drug in front of her, which was actually Chrysanthemum essence. Hau Ko accuses Sam Jie of providing information about Chun Hing's drug factory to the police. On the other hand, Sam Jie was shocked to learn that Hau Ko had set up the trap to test her. She was shocked to know that Hau Ko has never trusted her. Hau Ko tells her that he will never let anyone who betrays him off including the woman he loves most! Hau Ko then whips out his gun and shoots Sam Jie.
With her dying breath, Sam Jie tells Hau Ko that she has never betrayed him. Hau Ko checks Sam Jie's phone to see her sms exchange with Pak Kiu. Hau Ko finally realises that he has judged Sam Jie wrongly. He asked her about the listening device, which Sam Jie says she has no idea what he is talking about. Hau Ko holds Sam Jie and apologises to her, but it's too late.
Fa Si Lai feels uneasy the whole morning and is very clumsy. She broke some plates and cups and cuts her hand. She attributes her clumsiness to missing Sam Jie. Fa Si Lai then goes off to feed "Bobby" a stray dog who passes by the street behind the restaurant. When feeding the dog, Fa Si Lai runs into Chiu Sir, who also brings food for the same dog. The two of them start to bicker. Luckily, Yuk Bo runs out on time to stop the two. Yuk Bo then shares with Fa Si Lai the story of Chiu Sir and his beloved pet dog, Yan Yan. Yan Yan apparently died while trying to catch a thief and Chiu Sir was devastated.
Chiu Sir told the stray dog that he could not keep it as pet because he has a phobia after what had happened to Yan Yan. Suddenly, there was a robbery across the street. The stray dog barked and encouraged Chiu Sir to chase after the robber. Chiu Sir chased after the robber and successfully arrest him. Yuk Bo who arrived at the scene praised Chiu Sir.
Hau Ko returns home without Sam Jie. Yau Yau was surprised to see him and asked about Sam Jie's whereabouts. Hau Ko tells her that they never boarded the cruise. Hau Ko claims he could not leave Chun Hing behind and has broken up with Sam Jie. Yau Yau offers to help him contact Sam Jie but Hau Ko tells her not to call Sam Jie.
Yau Yau goes to Pak Kiu's house to ask them if Sam Jie has returned home. Pak Kiu and Yuk Bo immediately sense that something is amiss. They forced Yau Yau to reveal what had happened. Yau Yau tells them that Hau Ko has returned but Sam Jie is no where to be seen. Sam Jie is also un-contactable. Yuk Bo is worried but Pak Kiu warns her not to alarm Fa Si Lai.
Pak Kiu met up with Lap Man in at their secluded meeting place. Pak Kiu told Lap Man about Sam Jie's disappearance. Pak Kiu said he has checked with the immigration department and Sam Jie did not officially leave Hong Kong. He also mentioned that Sam Jie had looked for him earlier and asked him hypothetical questions. Pak Kiu said Sam Jie may have discovered Hau Ko's secrets.
Hau Ko sends Lap Man an SMS asking when he would return to Hong Kong. At the same time Wu Sir calls Lap Man too. Lap Man decides to return to Hau Ko's side to investigate Sam Jie's death, thus ignoring Wu Sir's orders to remain in the safe house. He meet up with Yau Yau and convinces her to continue to be his girlfriend. This is the only way they can find out what happened to Sam Jie.