Unriddle

A rich Indonesian girl disappears and the police have been asked to look for her. Officer Hu Xiaoman go in search for her and discover a human trafficking ring as well. The ring-leader Shan Fan and his partner Lin Zhengyi escape, but Xiaoman recognizes Zhengyi's back view.

Xiaoman catches Zhengyi but Yuze interferes. It turns out that Zhengyi is Yuze's mole. In the plan, something goes awry, and someone dies because of Zhengyi. Guilt-ridden, she vows that she doesn't want to be a mole again after this.

Yuze, Zhirong and Andrew go and pay their respects to Old Cai. They see Wu Guosheng there as well, and are reminded of the events 15 years ago. Zhirong tells Yuze he feels that Guosheng has been following him, and Yuze feels uneasy.

Yuze chases Shan Fan, and Zhengyi later sees Shan Fan using the money to bribe Yuze in hope that Yuze will let him go. In the midst of chaos, Zhengyi realises that Yuze and Shan Fan have disappeared, along with the money. Only a patch of blood is left behind.

Zhirong searches Yuze's flat and is questioned by Andrew. Zhirong shows Andrew a threatening note left behind in the flat. Andrew suspects that this may have something to do with the case 15 years ago. Andrew decides to tell everyone that Yuze succumbed to corruption and disappeared.

Xiaoman starts to investigate Xiuling's case and along the way discovers the sacrifice Xiuling's father made to look for her after she went missing. Xiaoman explains to Xiuling that what her dad did was because he loved her. Father and daughter were reunited.

Xiaoman starts to investigate the case of the missing children. Some of them return dressed as dolls. Xiaoman follows the trail of a clown and suspects that the clown has something to do with the missing children.

Xiaoman and Zhengyi return to the place where Xiaobo went missing. They discover that what Meiyue said did not tally to the evidence. Evidence pointed out that the time Xiaobo went missing was different from what Meiyue said. They suspect Meiyue may be hiding something

Zhenbang reveals the reason behind his motive for killing Cao Bo. He has loved Meiyue all these while, but seeing her unhappy in her marriage made him take drastic actions. He decides to take action against the problematic Cao Bo, to ease Meiyue's burden.

Xiaoman and Zhengyi trace Xingcheng's last steps before he was killed. They bring Meiyue along as well. Xiaoman suspects that Xingcheng was injured near Meiyue's office.

A teacher Shuzhen falls to her death from a building. Xiaoman believes it's the work of a perverted killer. A man was seen nearby before Shuzhen was killed. Xiaoman gets his face drawn out and it turns out that the man resembles Yuze. Is Yuze actually involved?

Guocheng tells Andrew that he felt that Old Cai wasn't intentionally killed by Xiaolang. He feels that it was Yuze who pressured Xiaolang to kill Old Cai. Yuze has always believed that Old Cai took the money, and with Old Cai gone, Yuze can now easily leave with the money.

Xiaoman and Zhengyi suspect that Zhongxiao has something to do with the women who have fallen to their deaths. They realise that Annie is the type of girl Zhongxiao is interested in, and decide to get her to lure him out.

Annie awakes at Zhongxiao's place and finds that she has been drugged. Jasmine has died and Xiaoman quickly tells Annie to leave Zhongxiao's. Xiaoman also asks Annie if Zhongxiao ever left his home, but a flustered Annie lies to hide the fact that she was drugged.

Xiaoman discovers that Zhongxiao has a secret past. He used to love his tuition teacher, but she was attached with a boyfriend. He bribes her boyfriend to leave her. But little does he realise that in her despair, she kills herself. Zhongxiao is wracked with guilt.

Xiaoman follows Zhirong to see what he is up to. Zhirong vaguely sees Dexing's shadow, and later on sees a suspicious man who seems to be carrying a gun. Just at the moment, a car speeds by Zhirong. Xiaoman senses danger and yells out to him...

Xiaoman traces Yuze's whereabouts to an old building. She sees photographs of Andrew, Zhirong, Guosheng and the rest. Amongst the photos, Guosheng and Zhirong's photos have been marked with an "X". The means that the only man left is Andrew.

Andrew grabs a gun and runs up to the rooftop, and Xiaoman gives chase. At the top of the building, Andrew points his gun at Xiaoman, with the intention to shoot her. Fortunately, Dewei appears in time, and shoots Andrew, but he gets injured in the process.

Xiaoman learns that the man who took Zhiyong away, Liu Zhiming, has been put away in a mental hospital. She goes and looks for Zhiming, but he is unable to give her any clues. As she is leaving, she gets knocked unconscious. She wakes up to find herself tied up in an un-used, dilapidated factory.

Xiaoman and Zhengyi rescue Yuze out, and send him to the hospital. The doctor says he has been very weak for a long period of time, and it would have been impossible for him to kill Andrew and the rest of the men. Zhiyong sneaks into the hospital, and Xiaoman gives chase. Zhiyong turns out to be... (to be continued)