Fifteen years ago, a female child was kidnapped on the way from school. At that time, Piao Hai Ying (Wang Tian Chen), who was an elementary school student, witnessed the girl being taken away. A few days later, the girl was found dead, and detectives couldn’t find the culprit. As time went by, Hai Ying started distrusting the police. Fifteen years later, Hai Ying is now a police officer and criminal profiler. One day, he finds a walkie-talkie that allows him to get in contact with Detective Li Cai Han (Du Chun) who is in the past. Police officers Hai Ying, Cai Han and Che Xiu Xian (Li Xiao Ran) then set out on a journey to solve cold cases.
(Source: Mydramalist)
