I love it that both Castle and Alexis dressed up for their poker lesson.
As soon as Esposito said his partner's body was never found, I pegged it that he'd turn up alive. It's kind of obligatory in fiction that no body means no death.
This is the kind of episode where the plot depends on the characters overlooking an obvious possibility or clinging too hard to an unproven assumption. They were assuming Thornton's fingerprint on the eyelid meant he was the killer, and it didn't even occur to them that he might've just found him dead and closed his eyes. I saw that coming well in advance too.
Also it was easy to figure out that Holliwell was the crooked cop once they ruled out Demming, since he was the only cop character left and a mystery wouldn't pin it on some guy who hadn't even been part of the story.
So pretty predictable overall. Still, it was nice to get a focus on Esposito and (to a lesser extent) Ryan.
And awwww, poor Castle's jealous.
By the way, there was a sign on the wall here that reminded me that this show is set at the 12th Precinct of the NYPD, a precinct famously featured in
Barney Miller and less famously in the WB's short-lived, updated
Tarzan series from a few years back (with Jane reimagined as a New York cop). So I decided to look up the 12th Precinct and see what I could learn about it. Turns out
the real 12th Precinct was abolished in 1916. So that explains why it's used in so many shows -- it's fictional. I guess it's the NYPD equivalent of the 555 exchange or Oceanic Airlines -- something unreal that's fair game for fictional use. The building used for the precinct exterior here is actually the 9th Precinct station.
The 54th Precinct is also fictional. According to
Wikipedia's list, there are quite a lot of numbers that aren't used for NYPD precincts, and I bet many of them have been used in fiction. I never realized that. Somehow I always figured the precincts used in fiction were real even if the characters weren't. I don't know why it never occurred to me they might be imaginary.