‘Castle’ Cast and Creator Reveal 8 Teases for Season 6

Castle is dipping back into what's been proven to work.

"A lot of what we're trying to do is deliver more of the same experiences [the viewers have] had and really enjoyed while continuing to let the show grow and breathe," creator Andrew Marlowe tells The Hollywood Reporter of the new season.

As for evolving the Castle (Nathan Fillion) -- who had a near-death experience -- and Beckett (Stana Katic) romance, Marlowe hints that the writers are exploring new territory in the stories they are able to tell because of the couple's engagement.

"We're approaching them the same way they're approaching each other: It's a new situation for both of them," he says. "Castle's been in engagements a couple times but never with somebody like this, and this is Beckett's first time through. As they're finding their comfort level, we're exploring and we're finding our comfort level."

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Known for diverse cases of the week, some of the crimes that take center stage on Castle include a Da Vinci Code/National Treasure-inspired mystery, a time-traveling suspect, Castle as a hostage negotiator and a case centered on a "creepy" serial killer.

THR also caught up with several castmembers about what's to come for season six:

Beckett's icy homecoming? The former New York detective has been holding down the fort in Washington, D.C. working alongside FBI Agent Rachel McCord (Lisa Edelstein), but a case involving an ex-'90s TV star brings Beckett back to the Big Apple. "There's a little bit of hazing involved when we let her back in. We're reluctant," Seamus Dever, who plays NYPD Detective Kevin Ryan, tells THR. "We're happy to see her but, 'Hey, you left us!' There's a little bit of that. She's got to earn her stripes back in order to be let back in as one of the cops -- one of the boys." The actor notes that when Beckett returns, her demeanor doesn't sit well with the others -- when she acts as if she's "taking over our job": "It's one of those things where you're like, 'Wait a minute, you're stepping on our territory here, fed girl! Are you one of us or one of them?' "

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Beckett's return to the NYPD? "If she doesn't [return to the precinct], let's just say there will be some long-term relationship that's going on and somehow the precinct has to get involved with whatever is going on in Washington," Penny Johnson Jerald, aka NYPD Captain Victoria Gates, tells THR. "If she does, we have to contend with on level does she return to? Will Castle return with her?"

Castle's engagement advice? The crime novelist hasn't had the greatest success with marriage, but hopefully his engagement to Beckett will change all of that. If there's one person who could serve as advice-giver, it'd be Ryan. "If there is some advice [Castle] gets, Ryan's going to be like, 'Stick with this one. You break her heart, we break your face,' " Dever jokes.

Ryan's impending fatherhood: With Jenny about to give birth, what does Ryan as a father look like? "He's going to want to be the dad who's always there, so being involved also means not getting to sleep so much. That might look like him with his eyes closed," Juliana Dever, Seamus Dever's real-life (and on-screen) wife, hypothesizes to THR. "He shows up without a tie, left his sweater vest at home .. Honestly, he'll feel naked all day," Seamus Dever jokes.

Is this it for Ryan and Esposito's bromance? "It's going to change the dynamic because they still buddy around and hang out together even while [Ryan is] married to Jenny. But it'll slow down more and more as she gets more and more pregnant," Jon Huertas, who plays NYPD Detective Javier Esposito, tells THR. "Once they have the baby [Ryan's] time is going to be limited and Esposito's going to be out there on his own and that's when Esposito might be looking for that missing part, which could be Lanie or someone else." Speaking of ...

Lanie and Esposito's romance revisited? "The next episode we shoot may have a little bit of a Lanie-Espo vibe to it, but I heard it's not so much sexy but serious -- maybe deep, raising the stakes a little bit," Huertas hints. He pointed to a conversation the two characters had about marriage while they were on a double date with Ryan and then-fiancee Jenny as the catalyst for their breakup -- mainly due to Lanie's lack of desire to fully commit. "It might come back to that or it might go the other way, where she's the one who wants to get married," Huertas posits. Even so, the Lanie-Esposito pairing has trouble ahead: "There may be something that trips up their relationship. There might be an instrument of destruction."

Rocky road ahead for Castle and Alexis? While Castle and Beckett are on the road to marriage, it won't be blue skies for Castle with his daughter, Alexis. "It's like when you have a best friend, they get a girlfriend or a boyfriend and you're not seeing them as much as you're used to, that makes you sad," Molly Quinn tells THR. "When they come back after the relationship gets rocky or they break it off -- I'm not saying that will or won't happen -- you're a little upset." Don't expect Castle and Alexis -- with new boyfriend in tow -- to smooth things over quickly. Marlowe adds that the father-daughter dynamic is "a little challenged this season" and is "testing the boundaries." "It's very tough going for a while," Quinn warns. "It takes them both being put in a situation that takes them completely out of themselves to come back together."

Will there be a wedding? Marlowe was coy when THR asked if there would be a wedding -- either with Castle and Beckett, or another set of characters -- only to say, "Fans will have to wait and see."

Castle airs Mondays at 10 p.m. on ABC.

E-mail: Philiana.Ng@THR.com
Twitter: @insidethetube

Philiana Ng