'Castle's' Stana Katic: Beckett Takes a 'Strong Step' Toward Committing to Her Future

Castle Stana Katic - TV Still: 11/21 - P 2011
Randy Holmes/ABC

Secrets have been playing a role in the fourth season of Castle and a sniper case will bring up a big one Detective Kate Beckett has been hiding from Richard Castle (Nathan Fillion) and company.

In Monday night's "Kill Shot" episode, a sniper is on the loose in New York City after targeting several victims. With the clock ticking and no motive, Beckett starts showing signs of having a dormant case of post-traumatic stress disorder that she tries to hide from her colleagues. The near-fatal gunshot wound Beckett suffered earlier this season starts to rear its ugly head again, sending "us spiraling into a rabbit hole of fear," actress Stana Katic revealed to The Hollywood Reporter.

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Beckett may find herself in an unfamiliar situation ("She's normally in control," Katic observes), but it'll be one that won't be easy to close the door on. "It's a real kind of psychological jouney," Katic says. "She can't get a grip on this fear that's overtaking her."

Thankfully she won't be battling it alone. With the help of Esposito (Jon Huertas), "she is able to come out stronger and more aware of how she wants the next part of her life to go," Katic says. Through Beckett's ordeal, more of Esposito's backstory will be revealed -- and a lot of it comes from Huertas' real-life story.

"Esposito is the only character who has experienced what she's experiencing throughout the episode," Katic says. "He's able to guide her in a way through the experience no one else could. Everyone else is incapacitated. They're reliant on Esposito."

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In many ways "Kill Shot" is a turning point for Beckett, who is still trying to search for the true killer in the mystery of her mother's murder. "This episode really brings Beckett a deep awareness that maybe the way she's been defining her life -- committed to bringing justice to her mom and all these other victims by solving their murders -- maybe going down that path hasn't been servicing her life all that fully," Katic says, "such as a potential relationship with Castle. It's a strong step in that direction for her."

She adds: "She commits even more to her future. Hopefully with Castle."

Katic talked more in depth about Beckett's current mindset earlier this month with THR. "People in life take on certain stories and say, 'I'm going to be defined by this story and I'm going to live up to every inch of this story,' " she said then. "This is that season where [Beckett] says, 'I've defined my life by this experience and I haven't actually lived my own life and let go.' We'll see more of that as we move on."

So while Beckett seems ready to focus more on what the future could bring instead of dabbling in the past, the following episode "Cuffed" (airing Dec. 5) -- which finds Beckett and Castle handcuffed together in bed with no recollection of how they got there -- will be a big indicator of whether something will finally happen between the two.

When asked what Beckett-Castle fans should expect from that hour, Katic was coy: "I think the 'shippers will love it."

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