These are the rules. Post a quote from the Canon and the next person has to post the next line and say what story it's from. It doesn't have to be a line someone's actually saying, it can be a descriptive sentence as well. It's quite easy to pick them, I just flicked through the canon at random and came across this little gem:

"Late that evening, as we sat together smoking our pipes in the village inn, Holmes gave me a brief review of what had passed."