family buys a large apartment in a high rise development and strange things begin to happen. Seems that years ago this was squatter territory and when the government reclaimed the land (The Chinese reclamation of Hong Kong?) the squatters were run off and many people killed. Now, this family consists of mom, dad, and Chi Lo, and Chi Lo mysteriously disappears from a birthday party for one of the neighbors kids. Mom sees him go over the wall of the high rise and while his toy tractor is found, he isn't. Mom apparently isn't too tightly wrapped anyway, so she and her husband conduct a frantic search for the child because the police aren't really doing much. It seems that somewhere in this huge apartment building there is one of the former squatters that has claimed Chi Lo for her own and moves around through the ventilation system. Mom figures this out, dad helps and ends up in hospital for his trouble while mom continues to hysterically search for her son, leading the neighbors to think she's quite unstable. This isn't a bad little thriller, much more a thriller than straight-out horror, really. There's some time spent showing how this former squatter woman reached the state that we see her in and you can only sympathize with her despite her appearance and the fact that she's taken someone else's child. Overall I kind of liked this but it could have used a bit more "oomph" or something.