We talked with showrunner David Amann about how the twist will affect Castle and what fans can expect in 2014.

ENTERTAINMENT WEEKLY: So Castle just got kicked out of the NYPD. How is this going to affect him moving forward?
DAVID AMANN: He is not ready to accept this reality, and so he is going to try to figure out a way to work with Beckett in spite of this. When we come back in 2015, a couple of months have gone by, [and] people have settled into their routine—Castle is not working with her, she’s working with Esposito and Ryan and everything has kind of achieved an equilibrium. And then he springs it upon her that he is now a licensed private investigator and in fact has been working hard at getting his license in the intervening period of time, which she had no idea about, and so he is attempting to use that to finagle his way into working with her. He’s working with her but not working with her; working with her in the capacity of a P.I. but basically trying to do an end run around getting kicked out of the 12th precinct, which of course doesn’t really go according to plan.

What does Castle as a P.I. look like? I’m picturing him buying the trench coat.

He didn’t buy the trench coat but he has a really great office. And I think that it is probably a long-held fantasy of his to be a private investigator and now he’s living it. It’s probably not working out quite the way he had thought it would.

How long is this going to play out? What do you want to say to fans who are worried this could be irreversible?
I want to say to those fans that, just as Castle and Beckett are meant for each other personally, I think they’re meant for each other professionally. Once Beckett gets over the shock of this, I think that she would prefer Castle to be working with her and he certainly would want that. But he’s committed a transgression from which it’s not going to be easy to recover, so this is his approach in the meantime. In his capacity as a P.I., he is able to weasel his way into cases and continue to work with her, though it’s going to be a little bit different. But I would also say that, at the end of all this, I think that he will not rest until her finds a way to get back into the 12th precinct.

Another big part of this episode was Castle being made an honorary mobster. Will that status come back into play?
It is in the sense that he was basically offered a favor at the end of that episode and I think it is possible that he may accept that offer at some point later in the season.

At the beginning of this season, you all talked about you were looking more into what makes Castle Castle this year.  Was this twist a big part of that?
It was a part because we think that for Castle, this is in a way a fantasy that he’s held for a long, long time, to be a P.I. I think he’s always sort of considered himself that. And now he’s actually going to live it, though I think the reality of it will be not quite up to his fantasy or it will certainly be different than his fantasy. That’s certainly part of it: We get to see another side of him, see him operate in a different capacity in some ways without Beckett. But I think there’s other things coming down the pike as well in terms of, as we get into the mystery of the missing time that we introduced earlier in the season, we’ll get into some other aspects of Castle there as well.

So you’re saying that missing time mystery will continue to play out?
Yeah, it’s sort of laying dormant. Obviously he pursued it as far as he could in episode 2 and they’ve kind of struggled with what do to since that period of time and then decided that we’re just going to get married and we’re going to move on. But I think that it’s coming back and it’ll probably be something that we touch upon in the two-parter coming up in February but we’ll probably deal with in a little more of a substantive way in the later teens of the season, perhaps early 20s even.

You all have had a lot of fun this year with episode’s, from the alternate reality to the Wild West. What do you have planned for 2015?
We hope that the audience will be delighted by this episode where Castle’s a P.I. We think it’s a lot of fun. The one after that is an episode where the victim is a telenovela star, so we’re sort of delving into that world and those characters. We think that one’s going to be another fun Castle episode. And then we get into the two-parter—those episodes tend to be a little bit more on the somber, thriller-y side. But in past seasons what we’ve often done is, after the two parter, there’s been a couple of episodes that are back to pattern, fun Castle episodes, and that will be the same this year as well.

Anything else you want to say to fans about this finale?
I don’t want the audience or the fans to think that we’re going to be telling Castle and Beckett separate stories in any way in connection with the P.I. move that we’re making with Castle. They’re still going to interact; his whole goal becoming a P.I. was to be able to work with her and he’s not going to let up until he’s able to do that. So we’re not going down the road of doing A, B stories where Beckett’s on one case and Castle’s on another. They somehow always are going to intersect, and they’re going to intersect in a significant way. And what’s fun is she still can’t really tell him things. She’s a cop, so if they’re working some aspects of the same case, they go home at night and he’s trying to figure out what she knows and she might be trying to figure out what he knows, so I think there’s fun that comes out of that because she wants to help him but she can’t because he’s sort of been forbidden from being part of the investigation. There’s a little bit of a dance that happens in some of these episodes while they’re at home having a glass of wine. We think it’s fun stuff.