Castle

[WARNING: The following story contains spoilers from the Season 4 premiere of ABC's Castle. Read at your own risk.]

"I remember everything."

With those words, spoken by Detective Kate Beckett in the closing moments of Castle's Season 4 premiere, the show kicked off what is sure to be a rollercoaster season of secrets.

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After narrowly surviving the gunshot she suffered in the Season 3 finale, Beckett (Stana Katic) tells Castle (Nathan Fillion) that she doesn't remember anything from the day she was shot — including the fact that Castle told Beckett he loved her. But in the premiere's final moments, Beckett confesses to her police-mandated shrink (Michael Dorn) that she she's been lying about her faulty memory.

But why? "She's scared to admit that she heard him because she's scared that the relationship is going to go to the next level and it could potentially ruin their friendship," creator and executive producer Andrew W. Marlowe tells TVGuide.com. "She wants it but she's not ready for it."

However, Beckett, who is clearly still a bit shaken up from her brush with death, is able to admit that she wants to work toward a relationship with Castle — after she finally closes her mother's murder investigation, which set this whole deadly chain of events in motion.

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"Beckett is struggling with some internal things that she really needs to put to rest," Marlowe says. "She intimates that she wants Castle, but she wants it to be a real relationship. She knows she's not as open and available as she wants to be in life, but she knows it's for a particular reason. So, if they can resolve Beckett's mother's case, that [removes] one of their biggest obstacles."

That's where things get really sticky. Although Castle wants nothing more than to help Beckett crack the case, he's got one problem: A mystery man (Geoff Pierson) with knowledge of Beckett's investigation warns Castle that if she continues digging, she will certainly end up dead.

"Castle is in this terribly conflicted position," Marlowe says. "It ends up being a huge sacrifice for Castle to ask Beckett to back off, because he's actually asking her to back off of the relationship."

Adds Fillion: "If she solves the investigation, she's saying she can be emotionally ready for a relationship with Castle. But if she delves into this investigation, she will be killed. That's very real. If you balance that with, 'Well, I might have a chance at dating her,' it doesn't really weigh out. He can't take that chance."

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Marlowe says that Castle will continue to try to solve Beckett's mother's murder on his own in order to protect Beckett. Meanwhile, look for Beckett's shrink to return at least a couple more times to offer a peek into Beckett's head (and heart).

The bright side, Marlowe says, is that even though they're not technically an item, their relationship is stronger than ever. "For all the people who keep saying, 'When are they going to get in a relationship?' they kind of already are," he says. "It just comes with baggage and complications. [These] are two people who we deep down know love each other but there's some significant secrets and significant obstacles that make it not the right time for them at this moment."

And if those secrets are revealed? "[It's] a powder keg," Marlowe says. "Either of those things can be a real ticking bomb in their relationship. So, there's a little bit of a delicate dance for the characters."

Castle airs Mondays at 10/9c on ABC.

What did you think of the premiere? Are you interested in the new dynamic between Castle and Beckett?