Warning, there will be Spoilers.
So, I'm very surprised they killed Mona off. But in the Books she was Dead awhile ago.
I'm more convinced then ever of the Twin theory, there is no dispute that was Sasha's hair.
Here is what gets me, as a Nerd and somewho studies the art of writing.
The Cop announcing "even though no Body was found" had me assuming of course she's not actually dead, that's Rule Number 1. They'll find away to explain all the Blood. Never even mind the fact that they couldn't be sure Mona was dead until they made sure all that Blood was Mona's, and there is no way they could've done that already.
But they then just showed her in the Trunk a few minutes latter.
They deliberately messed with us.