I guess I'll start with the subplot this episode is obviously named after. Um, with all due respect to Cas/Misha fans, I found that part pointless. Actually when he first wakes up in the Empty and starts going "Hullo? Hullo?! HULLO???!!!" I started laughing. And the whole thing with the "other Cas" who was really hammy and had a weird accent, who was that guy supposed to be? The dude in charge of the Empty? Cas kept demanding him to send him back and then boom, at the very end, he's back. Did I miss something? How exactly did that happen?
As for the rest, it was an interesting twist that the shapeshifter Mia had good intentions and was trying to help people. The baddie was that guy shifter that she'd had history with. As for the boys, I nearly wanted to smack Dean a few times the way he was kind of a d!ck to Jack, and then the way he gave Sam a hard time during their "session" with Mia. I was glad that Jack came through in the end when shifter guy was trying to shoot Sam. Dean did admit to him at the end that he did good. It wasn't much, but maybe it was a start. And it was good to see him apologize to Sam about what he'd said to him about Mary. Although he then asks him to keep having faith because Dean himself doesn't have any at the moment. Dean seems a bit all over the map but I guess I can understand why.
Again I enjoy Sam and Jack's interaction. This ep wasn't bad but again the Cas stuff seemed weird and nonsensical to me, unless I wasn't paying enough attention...