One rainy night, the body of Katy Lok, the only daughter of Macau Judiciary Police Detective Squad’s Inspector Yin Lok, is found in the wild. Based on the semen and DNA sample found in her body, the police arrest Manny, Katy’s classmate. 　　 　　Having quietly left the police after his daughter’s death, Yin thought that the case is closed. But one month after Manny is sent to prison, several more girls are brutally murdered in Macau. Yin begins to suspect that his daughter’s killer is still out in the world. 　　 　　Meanwhile, Yin’s young neighbor Ding Dong has long been abused and forced into prostitution by her single mother. Fortunately, Yin steps in and stops the abuse. However, just as Yin is getting closer to finding the killer, Ding Dong’s mother is murdered, and Ding Dong goes missing. To make things worse, all the evidence point to Yin being the killer. 　　 　　Now, Yin must both evade police capture and save Ding Dong before the killer murders her. On the rainy streets of Macau, a frantic pursuit is about to unfold.