I tweeted about Moriarty -- ie., Daniel Davis -- last night while watching, and someone replied to me, "Gd, I hope the writers are teasing & hinting at something, later in the season." As for the episode, the case was mildly interesting on its merits, but what I found more intriguing was seeing Sherlock take an "ends justify the means" attitude, both in his extortion of the Assistant Director of the FBI in New York City and, later, genuinely threatening the life of the insurance agent in order for force a confession. When the last scene went down, and the Assistant Director explained to Sherlock how it was going to be, how he'd written a confession himself that would implicate Joan, I realized, "Oh, this is going to blow up in Sherlock's face around episode 9 or 10. Either he's going to die and the confession will be found, or his computer or cloud accounts are going to be hacked and the confession will be released. Either way, this isn't going to end well."