Castle Season 6 will serve Kate Beckett's answer to Rick Castle's marriage proposal, which was left hanging at the end of the fifth season finale. Can Beckett possibly say no to Castle? Stana Katic dishes her thoughts on Caskett's future. New characters have also been revealed in spoiler reports.

Caskett shippers are hoping for their favorite couple's wedding in Castle Season 6. It could mean a long distance relationship for the two. But Stana Katic says things should work out fine. Meanwhile, spoilers hint a possible replacement to Beckett's post at NYPD. Who is she?

"I think they've been through a lot over the years ... And so it's justified in so many ways. Like, if they don't know by now that they're in love with each other, I think that we've missed the boat," Stana told Zap2it.

Stana also told Zap2it she does know what Beckett will say to Castle when the series returns in September. But she's not telling. (Aww, such a tease!) What if it's a big yes - could they work it out? Stana responds, affirmative!

"It's New York City and D.C. It's not that far," Stana said. "It also helps that he is a millionaire and a writer, which he can do anywhere. So how rough is that? He can afford to hire a private plane or two on her days off."

Susan Sullivan, who plays Castle's flamboyant mom Martha, has also spoken about the proposal in a separate earlier interview.

"I think they have to play this proposal out. So that's what I would hope it would be about and I would think, if she had a brain cell working, she would accept. So there. Quote that. And not get married until the end of season 8," Ms Sullivan told OTRC.

Caste Season 6 Spoilers (Lots!), New Characters Coming On Board

Two new characters will be introduced in Castle Season 6. One is related to Alexis, the other, to NYPD. Rick's daughter will meet this character called Pi (Myko Olivier) during vacation. Rick being a dad first, this Pi guy may or may not affect his impending engagement.

The other new character is a "no-nonsense, intelligent detective in her 30s." Her name is Rachel McCord, reports Spoiler TV. Will this Rachel replace Beckett at NYPD?

Actor Isaac Johnson is also joining Castle Season 6 in an unconfirmed status. He tweeted a photo of him with Nathan Fillion (Rick), saying they are screen partners for the day. On Instagram, Johnson posted what seems to be the Season 6 premiere episode script, and his name is listed as "federal agent." The script also shows Pi in a cooking scene.

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