You’ve just been informed that a murder is about to take place at your wedding. Do you...

a) Maintain your concentration and take the most direct route there in order to stop it…

b) Calmly and efficiently make your way through the crowd to see how you can help…

c) Gleefully skip out as if you’ve just heard the ice cream truck outside…

I think this shows their characters extremely well. Sherlock is focused on the problem and working on a solution even as he springs into action. John is in battle mode already, ready to take charge and take direction. And Mary? She’s all ‘Ooh, a nice killing, it’s been a while!’ And lest we say, yes well Sherlock thinks of murders as Christmas presents too, they all know at this point that Major Sholto is the intended victim. John’s good friend and possibly the most important guest at the wedding for him. Sherlock is not happy about that prospect. Mary is. Sherlock knows how Sholto’s death would affect John. Mary? What does it look like?