I see where both Castle and Gina are coming from... Castle is so used to being the mother and the father and being the best dad, that for someone else to be the favourite even for a minute, would be hard. AND to me, if someone is going to get a present like that, they should ask the rich well connected father to make sure he also isn't going to get tickets. But Gina had good intentions, so I think both were right. Gina should've checked with Castle, but Castle could've had a nicer reaction.
I kind of feel for Castle sometimes, Kate tends to criticise absolutely every idea he has, the Burger place was kind of a smart idea, even she agrees. But make him feel bad for it originally? I'd get to a point where I'd want to stop having ideas.
I like Greg and the whole Galaxy of Greg thing. He actually had a really smart plan. I also don't get how Kate can think he has an accomplice, it makes no sense and there's NO evidence of one.
I don't get why the killer pointed the cops to the agent. You pretty much set yourself up in the end, you didn't know about the hospital so to me that just makes it seem more like it was him.
I liked the ending, wish we got to see what happened to Amy. Probably found innocent.