Thaddeus and Emma
More plot intrigue for us.. Here was what I was thinking.
Emma was the previous leader of the Order of the Night. Killed by a bounty hunter, reason unknown. Most suspect one of the other clans. Because Mai chased down Thaddeus instead of the killer, they lost the trail of the bounty hunter.
What if the bounty hunter was hired by Sorin? He was tired of waiting for Emma to die (certainly wasn't going to happen of natural causes, now was it? ) She was quite good at what she did and rarely made a mistake. However, sending someone straight after her that she did not expect to be on her trail might just work. We can decide later who this person was.
I'm thinking perhaps Sorin feels people are getting close to the truth of Emma's death. He drops the ring that Mai found which belonged to Emma. A ring that he told the bounty hunter to bring back to him as proof that the elder was dead. He had been keeping it in a box, lord only knows where but now has dropped it in a place he knew Mai would find it. Knowing that the first place she'd take it to would be Thaddeus. Sorin is hoping that this will lead them back to the trail of the bounty hunter and away from him. Once the bounty hunter is killed he no longer has to worry. He might even consider killing the bounty hunter himself before they could find...her.
If he kills the bounty hunter which I think he probably should. He's not terribly stupid afterall, I believe we could possibly have the bounty hunter having stolen some of Sorin's things. In the event of her death, she had been carrying them with her because she felt he might betray her. This would lead either a tracker or one with Thaddeus's skills back to Sorin and thus possibly avenge her death.