
Yeung Pik Sum suffers from Schizophrenia and her illness causes her son, Yip King Fung, to suffer from Dissociative Identity Disorder. King Fung’s split personality, Chu Kei, becomes a handwriting expert and criminal profiler, who helps King-fung, an undercover agent, to uproot a criminal organization. However, a series of strange cases makes King Fung a murder suspect and his younger sister to be traumatized. Feeling guilty about abandoning her children, Pik Sum becomes a mental hospital assistant to protect her daughter, but she is unable to reconcile with King Fung... Superintendent Lip Shan invites King Fung to join the Special Crime Unit. Together with psychiatrist Wai Yui Kit, bomb disposal expert Yau Ngan Sing, forensic anthropologist Fong Yuen Chin, they deal with criminals with abnormal psychological conditions and solve complicated cases.

as Ip King-Fung / Chu Kei / Matt

as Yau Ngan-sing

as Wai Yui-kit

as Yeung Bik-sum

as Kong Ching-fun

as Fong Yuen-chin

as Ip Long-ching

as Nip Shan

as Leung Yat-sze

as Mok Hei Yan / Mok Hei Yu