Sitting in Saint Bartholomew's Hospital, the doctor says, "Your lucky to be alive, you only have a flesh wound, that mugger could have killed you." While the doctor went on and on about muggers, death, taking care of his wound, and discharge orders, Watson thinks back over the earlier events of the evening.
Watson was walking down the street, when a man came out of an alley with a gun, and issued him into the dark alley. They wrestled over the gun, a shot went off and Watson, slumped to the pavement. Two other men walked by, as the shot went off, and they laughed and kept walking, Watson said nothing as they walked by. He waited, still no-one came, he breathed out ratherly loudly, as he turned to Sherlock. He could barely see his his friend's outline in the dark. Which was good because it meant Sherlock couldn't see him, or the tears that escaped his eyes.
Sherlock quickly peeked out of the alley, no-one around, just as he knew there wouldn't be, now that John followers thought him to be dead. Sherlock said they had to make it quick none the less.
Sherlock said, Moriaty was, like himself, very much alive. Watson found that hard to believe, he had done the autopsy himself. He was positive he was dead, and glad of it. Sherlock said he didn't have time for details, and would explain more after checking out a few more things. Never questioning Sherlock's deductive reasoning, he didn't argue the point. It also explains why he, John, was being followed and by people wanting to see him come to harm, rather than to keep him safe, as evident by the two men that laughed and walked on.
They were in the process of just finishing up their plans for their next meeting place, when they heard the sirens. Someone had heard the shot, and it was time to Sherlock to go. Watson says, "What now"? Sherlock says, "Now I have to really shoot you". And even though Watson couldn't see him, he could swear he was smiling...
