This review has many spoilers, so if you do not want to read any spoilers, please go back
This episode starts with kinds of Chinese teapot. I guessed that it must be related with this episode, however it was not true. After the first scene of teapot, Sherlock took a phone call from his friend, and undertook a mystery case that some characters with yellow paint was spread out on the wall. When seeing this at first, I did not realise that why these things are related with this episode. While sherlock took the case, he discovered several dead bodies. He cannot find any other common point between bodies at first. But, he did not miss the point that when he found the bodies, there were always similar yellow characters which he saw before. Through searching evidence, finally he found out that the dead people were smugglers of ancient secret organization, and they had mark on their foot. Yellow characters were some kinds of code that used by smuggler organization, and those meant that the organization wanted something priceless. At the last scene, Sherlock solved the case, and the head of ancient organization ran out of the crime area. But, the head of organization talked to M(perhaps Moriarty) through laptop and M killed her with gunshot.
