A cop and his son move into a worn-down apartment building. The boy is first menaced by a neighbor girl and then goes missing. The father tries to look for him by knocking on the neighbor girl's door but finds that no girl lives there.
| Actor | Role |
|---|---|
 Leon Lai MingYu Fai | Yu Fai |
 Eric Tsang Chi-WaiChan Kwok-wai | Chan Kwok-wai |
 Eugenia YuanHai'er | Hai'er |
| TTing-Fung LiCheung | Cheung |
| LLau Tsz-WingYu's daughter | Yu's daughter |
 John Shum Kin-FunPhotographer | Photographer |
 Ting Chu-WaiPathologist | Pathologist |
| TTak-Ming TingJanitor | Janitor |
| HHeng WongDoctor | Doctor |