Plot
Definitely better than the last episode is the first thing I can say. Not exactly predictable, but it did follow a pattern - which felt kind of boring and less thrilling than a usual episode of Castle. While they tried to build the suspense by having Castle's life in danger, I doubt anyone watching believed for even a second that he was really going to die. The whole show is called Castle. It's just not probable. The only time I came close to believing a main character might possibly maybe die (or break both legs) was in Season 4 when Beckett was dangling off that rooftop, and this didn't even come close to the same level of tension. He didn't even seem to get that sick - he went along at 'mostly fine' until suddenly he was 'sweaty and not fine' and then he was 'collapsing and not fine'. But the symptoms didn't really feel very... symptomy. I was impressed with the way the DC team worked together, though, and I'm starting to like them. Yay! So that's a good thing. All in all, probably about as good as an average episode of Castle but in a different way. If it had been any other show I would have rated it more highly for the shipping moment at the end, but these characters are in a committed relationship. We should expect a moment like that every episode.
Music
Some nice suspenseful stuff, which added a sinister air to what would otherwise have been completely innocuous behaviour. I loved the reprise of Castle and Beckett's main theme at the end there - for those who want to know, it's called "I Just Want You" and it's by Robert Duncan. I have it on my iPod because it's totally awesome.
Acting
Fine from anyone, I didn't notice anything particularly bad. Beckett's face was intensely expressive, particularly towards the end of the episode, and I felt like she communicated really wonderfully that way. It was awesome.
Scenery
There were a few times when I really noticed this. Once was the moment when Castle was on the lawn and Beckett was leaning over him - and it felt like a perfect reversal of that moment in Season 3 when she was shot. The other was when Beckett was hunting Parker down in the back garden of the Secretary's house and that fountain was there. It was just such a cheerful little fountain, burbling away, and it really just lended some atmosphere and a sense that the scene was grounded in reality which I liked a lot.
Sexism
The fact that the women had their eyes caked in make-up and the men didn't? Yeah that kind of annoyed me. It doesn't help that I'm not one of those women who wears make-up on a day-to-day basis anyway, so not only do I notice it but I don't believe it's necessary. If my fiance was dying, I wouldn't waste a single second on applying a fresh coat of mascara. Apart from that, nothing glaringly obvious.
Bechdel Test
1. It includes at least two women, (Yes)
2. who have at least one conversation, (Yes)
3. about something other than a man or men. (No)
Just be aware, I take the conversation step to mean a conversation with just the women. The only conversations McCord and Beckett had alone were about Castle, the Secretary of Defence, Bronson or Parker. They spoke about Valkyrie, who isn't a man, but only in conversations with men. So yeah. 2/3
2. who have at least one conversation, (Yes)
3. about something other than a man or men. (No)
Just be aware, I take the conversation step to mean a conversation with just the women. The only conversations McCord and Beckett had alone were about Castle, the Secretary of Defence, Bronson or Parker. They spoke about Valkyrie, who isn't a man, but only in conversations with men. So yeah. 2/3