Castle Season 6, Episode 4 ("Number One Fan") treats the Caskett fans to a sweet NYPD precinct kiss. Rick Castle (Nathan Fillion) hesitates, but Kate Beckett (Stana Katic) tells him she's not officially back at work -- yet. The couple's wedding is likely to happen this season. Stana teases an upcoming issue ahead of D-Day.

Spoiler Alert: This feature contains spoilers from the next episodes of Castle Season 6. Read at your own risk.

Time Will Tell: A Castle Mystery for Becket at NYPD

Next week, Nathan gets to geek out in a "time travel" episode. Castle Season 6, Episode 5 is called "Time Will Tell." This is expected to delight sci-fi fans of "Firefly" and "Serenity," where Nathan starred as Captain Malcolm Reynolds.

So much was said about Kate Beckett's Washington job before the season started. It turns out the whole mini-chapter was good for three episodes only. In Castle Season 6, Episode 4, Kate Beckett finds her way back to her New York job. It seems Stana Katic and Nathan Fillion will both be NYC-based for the rest of the season.

"Number One Fan" opens to a troubled Kate. She wakes up Castle early in the morning to vent about not knowing how to exist in a universe where she's unemployed. By the end of the episode, the problem's been solved.

The time travel episode next week will show Beckett back in New York with Ryan (Seamus Dever) and Esposito (Jon Huertas). The team plus Castle will be "investigating a murder suspect who claims he's from the future."

Meanwhile, Stana reveals an upcoming pre-wedding issue, possibly a minor conflict, in an interview with TV Line.

Castle Season 6 Wedding? Alexis Not Happy!

Molly Quinn, who plays Castle's daughter, has earlier teased fans, saying the Caskett wedding is probably not going to happen so soon. Stana explains:

"I think that this is a matter for a father and daughter, and a daughter knows that no matter what the father is, he's going to be the same, in spite of the fact that he's entering into a new relationship," she told the entertainment news site.

Stana downplayed the possibility that Beckett and Alexis will have some talk to resolve any pre-wedding issues. The issue is largely between Rick and his "little girl."

Me to guy in Serenity shirt- Nice shirt. Guy- HEY! YOU'RE IN THIS! I ALWAYS HOPED THIS WOULD HAPPEN! Me- Keep hope alive.

— Nathan Fillion (@NathanFillion) October 9, 2013

In Australia, the Castle Season 6 premiere ("Valkyrie") will air on Seven beginning Oct. 6. The new season premiered on Sept. 23 in the U.S. channel ABC.

More 'Castle Season 6' and TV Guide Features:

Castle Season 6 Episode 3 'Need to Know' Review, Stana Katic Talks About Kate Beckett Post FBI Termination [SPOILERS]
Arrow Season 2 Spoilers: Stephen Amell Teases 'Awesome' Premiere; Olicity, Dig and Black Canary Level Up [PHOTOS]
The Walking Dead Season 4 Premiere, Spoilers: Scott Gimple Teases 'New Virus,' Explains Why 'Nothing Happened' in Opener [PHOTOS]

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