I thought it was a great episode. Plenty of twists and turns, with more to come I'm sure.
The pharmacist twist was interesting. I thought he'd been made to look a bit too pathetic beforehand, though (his daughters taking the piss out of him, tripping over multiple times on the path, etc). I suppose maybe to make him seem incapable of murder.
Not sure how he can frame anyone else or make it look like a suicide, though, as she'll have injuries to the back of her head. Also, I'm pretty sure he closed the door with his hand on the way in, because he didn't put his gloves on until he was in the house and the door was closed behind him.