'Castle' Postmortem: EP Talks Midseason Finale's Big Firing, Breakup and What's Next

Castle - H 2014
Courtesy of ABC

[Warning: Spoilers ahead from Castle's midseason finale, "Bad Santa."]

Castle's title character finally crossed a line he couldn't charm his way out of.

After a detective was shot and killed — and the D.A. learned that Castle (Nathan Fillion) had been cooperating with the mob during the course of investigating the case — the writer was banned from working with the NYPD.

And though Castle still has his primary job (as a best-selling author), he won't be content to let go of his investigations with the NYPD. Instead, when the show returns from its holiday hiatus in 2015, Castle will work toward becoming a licensed private investigator.

Castle executive producer David Amann spoke with The Hollywood Reporter about what Castle's firing will mean for the 12th precinct, Lanie (Tamala Jones) and Esposito's (Jon Huertas) breakup, bringing back 3XK and more of what's in store in 2015.

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Now that Castle has been banned from working with the NYPD, what comes next?

Castle loves Beckett (Stana Katic) personally and professionally, and would love to continue working with her, and … in January, he will finagle his way into becoming a licensed private detective in an effort to continue to work with her, and do a bit of an end run around the mandate that has been laid down. Of course, this is not [all] going to go according to his plan.

How is everyone going to react to losing Castle as a full-time presence at the precinct?

When we come into the next episode, a period of time has gone by, so everyone has acclimated to the fact that he's gone. They all have continued to do the job they had before he appeared on the scene. That isn't to say there isn't an effect on everybody, Beckett in particular. And it also [impacts] Ryan (Seamus Dever) and Esposito. In Ryan's case, he starts to take it upon himself to offer the Castle-esque source of theories because Castle isn't around to do that, so he anoints himself the new Castle, or the mini-Castle.

And do people react well to Ryan's attempts to be that mini-Castle?

I think most of the time it's played for humor. (Laughs.) I don't know that any of his theories will go toward cracking the case, like Castle's were.

This appears to be — at least on the surface — the biggest shift to the Castle and Beckett partnership the show has made. How much will their interactions and the way they solve cases change?

I think he gets into this [job at the 12th precinct] to work with her, and he will continue to use his status as a PI to do that. So they will be able to professionally [interact], one way or the other.

Is this going to be an arc that lasts a few episodes, the season or the rest of the series?

His ultimate goal is to try and get back to the 12th precinct, but I think there's quite a hill to climb to do that. So I think in the meantime, or until such time occurs, he'll be working as a PI.

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Will Castle and Beckett be working on separate cases, or will they still be working on the same cases?

Their cases are going to intersect, at least in this run, so we'll still have fun Castle-Beckett interaction and conflict over work; it'll have a slightly different quality to it. They may be working different aspects of the same case. But they do cross [paths]. We're not getting into a situation where we have separate A/B stories where Beckett's doing one thing and Castle's doing another. They'll intersect with each other in some fashion.

This is a move that might worry some fans of the show. What would you say to reassure them that this isn't fundamentally changing the series they love?

Castle is determined to work with Beckett, and they'll see this [shift to him as a PI] as a means of doing that. I think, ultimately, if it doesn't result in them working together in the way he wants — the way they both want — they'll find some other way to, somehow, reconnect professionally. If the question [from fans] is, is this permanently going to turn into the Castle is a PI show, I think that [the upcoming arc] is a result of a situation that has arisen that has removed him from the 12th precinct and from Beckett, and he'll be working tirelessly to change that.

Good to know. The other big event from the midseason finale was that off-on couple, Lanie and Esposito, opted to end their relationship again. What comes next for them?

It's going to result in, for one thing, a little bit more of Esposito exploring his life as a single man. So I think there are going to be some fun storylines coming up addressing that.

In an earlier episode this season, "Kill Switch," Lanie's name was the first thing out of Esposito's mouth when he was in life-or-death danger, which seemed to indicate they might actually have been heading toward a more serious commitment. As writers, was there ever the consideration to stick with the couple, or was it always the intention that they'd be breaking up again fairly quickly?

Look, I think they have kind of come together and come apart a number of times over the series. These are two people who have a great deal of affection for each other and a great amount in common, but they're never quite at the same place with each other. So there is the possibility that they may find each other again, but in the meantime, they're going to be amicable and work colleagues — and the romance is going to be on hold for the time being.

That makes sense. What can you share about what's in store when the show returns in 2015?

Castle as a private investigator offers some delightful things to the audience. You're going to see Castle in a job where he doesn't have a tremendous experience doing [it], so there's a lot of fun to be had with that as he tries to find himself in this new career path. There is one [episode] that revolves around the death of a telenovela star that Castle has been associated with. Also, we felt like in any version where Castle is a PI, we have to do something that speaks to the film noir history of PIs, so there's something like that coming up as well where he gets involved with a conspiracy in which he is at the center. So those are a couple of things coming our way.

You mentioned a mystery in which Castle is at the center — are you referring to his missing months?

It doesn't have anything to do with [that] mystery.

When will you touch on that next?

We're going to be touching on it in the mid-teens, but we're probably going to be getting into it deeper in the late teens or back part of the season.

Is the upcoming two-parter arc where you'll touch on Castle's mystery?

We'll touch on it then. There's going to be a revisiting of some extent of the 3XK story. There's going to be a case that comes up where Kelly Neiman's (Annie Wersching) name appears, who, as you'll remember, was the plastic surgeon disciple [of serial killer 3XK]. So that will kick us off on an interesting mystery for those two episodes … [they] will be a big, kind of epic couple of episodes.

Castle airs Mondays at 10 p.m. on ABC. What did you think of the midseason finale? Hit the comments section below with your thoughts.

Twitter: @marisaroffman