Stana Katic and Nathan Fillion Stana Katic and Nathan Fillion

It's the question Castle fans have been asking since the series premiered: When will Rick Castle (Nathan Fillion) and Kate Beckett (Stana Katic) finally get together?

"True Caskett fans are going to be well-pleased by the end of this season," Katic told just prior to Friday's PaleyFest event, which was moderated by TV Guide Magazine's William Keck. "We're well on our way in that direction."

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The intrepid novelist and tough detective have been continually dancing around their feelings, with Beckett feigning amnesia after Rick told her he loved her when she was shot, and Beckett being gut-wrenched to learn that she wasn't Castle's first muse. That honor belonged to Sophia (Jennifer Beals), whom he had slept with and who also turned out to be a Russian spy.

Beckett has been wanting to tell Castle that she heard him say those three little words from the beginning. "Beckett was just wanting to find the right time to do it," Katic said. "She doubts herself a little bit in wondering whether he feels the same way. When the two-parter happened, Beckett wondered if it's all just in her [head], and she's not as special to him as she thought she was."

Meanwhile, Castle has been secretly investigating Beckett's mother's murder case, while keeping Beckett in the dark for her own protection. "There's going to be some secret-divulging before the end of the season," Katic said. "I can't imagine that it would be very comfortable to know that the guy you're in love with has been holding you back from solving the biggest case of your life."

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Those secrets will come pouring out soon, with creator Andrew W. Marlowe noting that the March 19 episode, "A Dance With Death" is "the last calm episode before some interesting stormy waters for the characters. This was the season of secrets. Those secrets are going to start to come out and they're going to have repercussions for both of our characters and will lead to a very exciting, very emotional conclusion to the season."

Last season's finale was a heart-pounding game changer that climaxed with Beckett being shot at Captain Montgomery's funeral, whereas "This finale is going to be emotionally big and no fan of the series should miss it," said Marlowe. "There may be some element of [danger], but it really is about the emotional storytelling in that one."

Castle returns Monday, March 19 at 10/9c on ABC.