By Sandra Gonzalez
Updated September 20, 2011 at 06:00 AM EDT
Eric McCandless/ABC

WARNING: Do NOT read if you have not watched the season premiere of Castle. Enter at your own risk.]

Castle opened its fourth season last night with a highly emotional hour that found Beckett (Stana Katic) shot, nearly dead, miraculously saved, bed-ridden, healed, boyfriend-less, and then stricken with PTSD all within an hour. Sounds exhausting, doesn’t it? And we haven’t even gotten to Castle…

At some point between “nearly dead” and “miraculously saved,” Beckett told Castle (Nathan Fillion) that she didn’t remember anything about the shooting. That means she didn’t even recall his “I love you” at the end of last season. Wah-wah. (Oh, and she was totally lying.)

So, by the end of the premiere, here’s what we knew: Castle loves her, Beckett loves him, and they can’t do anything about it because she’s not ready and he knows she won’t be ready until she does more digging into the ultra-dangerous case of her mother’s murder. And where does that leave our favorite couple — and the viewers? EW rang up executive producer Andrew Marlowe a few days ago to chat about the premiere and find out what’s to come for this conflicted couple.

In sum? This is only the beginning…

ENTERTAINMENT WEEKLY: So, let’s start off with the obvious question: Did you conclude tonight’s episode off where you did to personally torture me?

ANDREW MARLOWE: Yes. You were on my mind when I wrote that.

Okay. In all seriousness, why wait to address what she heard Castle say? Why not tackle it in the season premiere?

To me, what I’m trying to do is set up something that is going to bring an interesting and complicated level to the Beckett/Castle relationship for, the very least, the first part of the season. Both of these characters are very complicated characters. It’s very clear, given what Beckett has gone through, that she wants to have this relationship with Castle, but she’s worried she might blow it. She’s worried about sacrificing the friendship, and she’s haunted by this ghost of her mother’s murder. She’s come to the realization that she’s had these walls up inside, and that’s why none of her relationships have really worked. That’s why she hasn’t really focused on them. She needs to have those walls come down. But if she acknowledged that she had heard Castle, then that’s just going to be the elephant in the room. Then she’s either going to have to act on it, or it’s going to destroy the relationship. So it’s easier for her to act as though she didn’t hear it, but it certainly changes her perception of him now that she knows.

I feel like Stana Katic communicated that very well throughout the episode.

There was that great scene on the swing set where she says, “I’m not going to be able to have the relationship I want…” and she looks over at him. If you’re a fan of the show, you know she’s looking at him for a reason. But we wanted to make it more complicated for them. In order for them to have a relationship, as far as the Beckett character is concerned, she needs to put aside some of this emotional baggage that she has and resolve it. Castle is completely on board for that. He’s like, “You’ve just given me hope.” Then he gets this phone call. Now the thing he wants most — which is to resolve this [for Beckett] — the cost might be losing her completely. So it puts our characters and our audience in a complicated situation. And it puts our guys in an interesting situation for the season because they both have these huge secrets from each other. Castle has had this conversation with this mystery man, who assures him that if Beckett investigates and if Castle let’s her run out into traffic again, it’s not going to end well. And this goes against what he wants. And Beckett has this monster secret from Castle in that she heard everything, but she can’t do anything about it.

How much is Beckett’s mental health going to be addressed this season?

Some of the PTSD and some of the emotional scars are going to pop up a couple of times through the season. IT’s not something we’re going to hang on every episode. There were a lot of pieces for us to pick up from the season finale and in writing the season premiere. We tried to deal with them all honestly and authentically. We didn’t want to sweep anything under the rug. So the season premiere was really about getting us to a place where people could get back to the things they love about Castle and Beckett — the ability of these two people to have banter and get on each other’s nerves in the right way and in a fun way. And it was about continuing to deepen a relationship they both want, but life has become complex for them. So it’s not going to happen in this instant. And to all those ‘shippers who are frustrated that they’re not in a relationship now, I’d say they are in a relationship. It’s just a complicated relationship and they have a lot of untangling to do before they can get to the purest form of a relationship.

Well, at the end of last season, you said it would all come together. You were true to your word, I’ll give you that.

Well, I was lying. I didn’t know what I was doing. [Laughs] But we were trying to do it in a fresh way, but also in an authentic to our character.

NEXT: ‘Deep down, he knows…he’s met this person who he can spend the rest of his life with.’

Getting a little more specific, the screen we saw with Castle’s own investigation into all of this was pretty cool but also scary considering the threats. How much are we going to see him getting into his own investigation?

It’s not something we’re going to touch on week to week. But we know that Castle wasn’t to resolve this. And if she’s being threatened, that doesn’t mean he can’t poke around a little bit. Rest assured, that stuff is going to pop up throughout the rest of the season. But it would be unauthentic to think that Castle was just going to sit around and do nothing for the rest of the season. He knows what he needs to do to have this relationship. He has to talk her out of it doing it, which is a very difficult and painful thing for him to do because he’s basically talking her out of following the trajectory that would lead to what he’s looking for. So he’s going to take responsibility for it.

So Beckett cut Josh (Victor Webster) loose in this episode. I hate to say it, but I think a lot of fans are going to cheer for that. I mean, he’s a great actor, but…

We know how people feel about him and that’s how we wanted people to feel about him. We wanted people to see Josh as an obstacle. I think Beckett really expressed her relationship with Josh very well in this episode, and she expresses her relationship with some of her last guys very well on the swing set. I’m glad that came across.

One question I wanted you to clear up was about Castle. I sort of felt like at some point during the episode, he completely regretted telling Beckett that he loved her. Or am I reading that wrong?

I don’t think that he regrets saying it, no, because he didn’t know how that situation was going to go. I think he regrets not being able to act on it. He knows that if he pushed it now, he wouldn’t get what he wanted. He did it in a very emotionally raw moment and complications ensued. But then he found a pathway. And there are obstacles in that. I think what Beckett is afraid of, ultimately, is losing Castle. If they get into a relationship, she could lose him because she’s not ready and she’s not sure he’s ready. She still has questions about the kind of guy he is. We’ve seen him grow up a lot in the last three years, but I think any woman getting into a relationship with a guy like this on that level would have those questions. And he knows how he feels about it. But given what he found out in the aftermath, he wants to do it the right way. He wants to have the right relationship with her. Deep down, he knows — whether he’s expressed it to himself or anyone else in the universe — he knows he’s met this person who he can spend the rest of his life with. He just doesn’t know how to go about it because he’s never done it successfully.

Neither of them have.

Exactly. There’s hesitancy and fear. There’s that desperate need to reach across the way, but thinking that if you do that, you’re going to f— everything up.

Lastly, I have to tell you how much I loved these lighter moments involving the new chief (Penny Johnson Jerald), particularly watching Ryan (Seamus Dever) and Espocito (Jon Huertas) react to the new chief. Were you just absolutely dying watching Ryan act paranoid?

That was a lot of fun. Seamus did a great job with that and Rob Bowman did a great job directing and finding these small moments to show how it’s impacted everybody. But you can see it’s much different than when Capt. Montgomery was there, when Beckett was the really good student who never needed a hall pass. Now, she’s accountable and she doesn’t like it. That’s an interesting dynamic. And last season, it felt like everyone was comfortable with Castle, very accepting of him. Then having this person come in and say, “What the hell are you doing here?” was a lot of fun. It gives Nathan, as an actor, and Castle the character something to push against and brings out a lot of charm in the character.

Castle fans, follow Sandra on Twitter! @EWSandraG