Radley starts to lead him along, but pauses at the threat and looks back over his shoulder. "Is it really wise to threaten the person who's trying to help you?" he says mildly, but with a hint of warning. He doesn't appreciate this guy's attitude. He hadn't been happy to be kidnapped, but he hadn't threatened the ones he had run into on his ship. Of course, he doesn't know where this guy came from or how much reason he might have to be suspicious of anyone and everyone.