Sherlock is being strangled at Soo Lin’s flat; pretty badly too. It looks like he passes out for a few moments and can barely talk afterwards. The attacker simply stops for some reason. Why? Because John, sarcastically bitching outside, has just said that he is Sherlock Holmes. Good luck for Sherlock that John is a Grand Master of Snark and the Black Lotus is entirely populated with total morons. It saved his life.