This is the Pearl. A BASE jump from 1,000 meters up gives you roughly about two kilometers...

Inspector Wu: [figuring out how Botha's team plans to escape] This is the Pearl. A BASE jump from 1,000 meters up gives you roughly about two kilometers descent distance. [drawing on a map] Inspector Wu: Now, if you're right, they will land somewhere within this circle. Somewhere open and flat, secluded. Now, they wouldn't go for Victoria Park. There's too many trees to get hung up on. South, they wouldn't clear the peak. North, maybe, but it's a longer haul to an open spot. Sarah Sawyer: What about this? What's that? Sergeant Han: That's nothing. It's a construction site. Bay Dredge. [in Cantonese as Wu circles it] Sergeant Han: You can't seriously be considering this. For all we know, she could be in on it. Sarah Sawyer: You think I would willingly trap my own children in a burning building? Sergeant Han: I think you could be playing a role. This could all be part of your husband's plan. Sarah Sawyer: [to Wu] Take me there. If I am wrong and it's empty, then what have you lost? But if I am right, this might be your only chance to catch the people responsible for this whole thing.