Bai Qingxiong (Chen Hanwei) has been with the police force for more than 20 years. He has come across many unsolved cases and witnessed the pain and suffering of victims’ families unable to find closure. To address this, he opens a detective agency, CCI, to investigate unsolved cases. Two others join him: Huang Yuyang (Rebecca Lim), who used to be his subordinate in the police force, and Hong Junyan (Desmond Tan), who has no experience in criminal investigations. Qingxiong does not receive any cases in CCI’s first year. He helps out in the restaurant run by his wife, Yamamoto Atsuki (Lynn Poh). Lan Haifeng (Yusuke Fukuchi) hires CCI to nab the murderer of his girlfriend, Li Xiaoqing, who was found dead in the bushes in a park; she was raped. It happened eight years ago, in 2008. At the time, the three suspects were Tang Zhenguo (Louis Wu), Adam Teo (Ryan Lian), and Lan Haifeng. Lan Haifeng was the prime suspect. He was acquitted one year after detention. Qingxiong was one of the investigating officers then. Xiaoqing's parents believed the murderer was Haifeng as he had threatened to kill Xiaoqing after she initiated a break up. Yuyang and Junyan tail Adam, who has become a pimp. To get close to him, Junyan pretends to want to hire a prostitute. Instead, he is stripped naked and chased out of the brothel by Adam and the prostitutes. After much probing, the three of them clear the suspicions surrounding Zhenguo and Adam. Haifeng remains the major suspect. Qingxiong finds out Haifeng is leading a normal life. He does not have a girlfriend, but has a domestic helper named Liang Meiyun (Tin Wai Wai), who cleans his house regularly. From the evidence gathered, Chen Jieming is found to be connected to the case. Xiaoqing was a volunteer at Rainbow Charity. She had counselled Jieming, who is slightly autistic. Junyan and Yuyang follow Jieming to the crime scene. Jieming is seen mumbling to himself and behaving strangely. It turns out that Jieming had a crush on Xiaoqing
