In response, he rattles weakly on the door. It's incredibly obvious (and terrifically painful) that Ling doesn't want to hear him, see him, or have anything to do with him. But he hasn't come all this way to speak to Ling through a door. He needs it to be done properly, for it to be a real face-to-face encounter.

Otherwise he could have left the boy a message. But Ling deserves better.