Old man in china town

During a night Portrait chase in China town, I hear @pash.c telling me: Younes!! Turn!! look behind you!! Then between the crowd, a weird metallic shape appeared. I had to act fast, the goal is to take his portrait, but most importantly, I have to take as it is, natural. I went quickly in front of him, smiled at him, but he saw me coming with my camera and understood everything, stopped, smiled back to me. Click! One shot was enough, I've shown him the shot, he was happy about it, smiled and went on his way. No word has been said, and same time hundreds of them.