SURPRISE!CAS IS ALWAYS FOR THE WIN!
I've actually wondered why Castiel didn't notice that Sam's soul wasn't inside of him. I remember distinctively last season all he had to do was touch someone and he could tell whether or not their soul was still inside of their bodies (5.14 "My Bloody Valentine" in the morgue, for example) But it looks like Castiel is performing the same kind of ritual that he did on that kid on 6.03, so it means he's trying to figure out what happened or even what did this to him.
It also looks like we have Campbells in that episode, boo. But at least we know that something is up regarding souls and whether they have theirs as well. It's something to go by.
ALSO WE HAS MOAR CYLONS THAT JOIN THE PARTY. HELLO SIMON! \O/\O/\O/
But this has me questioning with this Alpha thing. So is Alpha like, the new YED? Breeding Sam to be his "perfect animal"? Better, more efficient hunter and fighter and killer without a soul to get in the way? idek