I agree about not trusting the promos at all. I'm thinking Dex may even get arrested (something minor) on purpose. There would be more cops around him in both the house and station arrest scene. And there is only one short setence of dialog in the arrest scene as well. Maybe Dexter needs to spring Hanna and ask her for one last favor. Plus if Dexter is in jail and another BHB crime scene appears, he's safe. I'm thinking Dexter is in jail, sends Hanna to do/kill something. She walks into a trap. A BHB room, tranq injection from Deb, a short, well written conversation takes place, and Deb plunges a knife into Hanna. Or the season ends with Deb holding the knife over Hanna dressed very much like Dexter would be. It would be a full circle ending. "If" Deb took the pills, I think she would kill Hanna to free Dex once and for all from BHB suspition. But there is a lot going on in that promo. Whatever happens, I'd bet the arrest scene takes place about 25 minutes in to "Surprise Motherfocker" and however it ends, that will blow the promo away.