An episode of Castle that has a more serious tone, allows Ryan a chance to shine, and shows the team coming together to protect one of their own is already going to get plenty of kudos from me. But then, there’s also mention of the 3XK killer? Oh, it’s on.

So it shouldn’t be too surprising that “Kick the Ballistics” is my favorite episode of the season thus far. It’s a case that at first appears to be just a routine killing, but matters then take a spin for the worse once Ryan’s old gun is determined to be the murder weapon.

Ryan: That weapon was issued to me by the city of New York. I let it out of my hand and now a girl is dead. Do not tell me this isn’t my fault!

Good cop or bad cop? What does that even mean? For Ryan and Castle this week it means everything. Continuing on from last season’s “3XK”, this episode marks the return of the gun that was taken from Ryan almost a year ago when it’s used to murder a young woman who’s body is then hidden in concrete. (“I’m looking at the concrete evidence right here.”)

Seamus Dever stole the episode this week in my mind with his angsty portrayal of Ryan, a cop who feels responsible that his weapon was used to commit a crime. Which I don’t necessarily understand, but never mind that because Castle doesn’t quite get it either. (“It’s a cop thing, Castle.”) One quick comment from Beckett, and Castle’s then off wondering if he really fits in with the team the way the rest of them do.

What Castle doesn’t realize though is that being a cop means a lot more than having a badge and a gun. It’s about doing the right thing, putting away criminals, and keeping people safe. Thankfully, his mother is able to put it all into perspective. (“Your ‘play acting’ once saved New York City as I recall. Be there for your friends. Stand beside them. Work together. That’s plenty useful.”)

Which brings us to the Ryan and Esposito bromance. I’m really happy with how the show is allowing the secondary characters to shine this season instead of only focusing on Castle and Beckett. I especially loved seeing more of the friendship between Ryan and Esposito again this week as they backed each other up and hilariously went undercover as if they were in The Fresh Prince of Bel Air.

And even though 3XK killer himself didn’t actually show up, there were still a lot of ramifications to be found from his indirect involvement in the shooting. The actual murderer Philip Lee claims the 3xK killer gave him information about where he was going and what name he would use when he got there, but Castle, rightfully so, doesn’t believe he’d give out accurate information. They decide to not take the deal and let Lee go down for murder. (“Damn, Castle. Look at you thinking like a real cop.”)

Notes and Quotes:

It was great seeing Billy Lush (Liam on The Chicago Code) in another series.

How hilarious was it that Castle suavely took a picture of Ryan and Esposito in their getup?

Is there no rules against using an informant in dangerous situations? The seedy cop did it with that woman in this episode, and Carrie did it in Homeland.

Next week:

Murder at the museum. Beckett is jealous. And it’s The X-Files Kristin Lehman!