In the tunnel Nick finds the stream of water, not clean but not sewage, more comfortable to walk in than the access path, especially given his height and amphibious nature.  A mantis like GenSect walks toward them, on the ceiling, and tells them the mall access tunnel is just ahead.  The bug looks familiar to Nick, but he can't place him.  Nick then goes to the mall, and the Lurker hides out at the trapdoor for a while, snatching jumpers who get too close, then finishing his rounds and bringing fresh spider meat home with him.