If you’re a Castle fan fretting over what designs the series’ new showrunners may have on your beloved newlyweds, Nathan Fillion would like to share some reassuring words.

“Don’t be worried,” he said with a smile while stopping by TVLine’s Comic-Con interview suite at the Hard Rock Hotel.

Fillion and his Firefly co-star Alan Tudyk were there to talk about their latest project, Con Man — a separate post on that project will be up later — but the actor took a moment to answer Michael Ausiello’s queries about what the Castle‘s regime change might mean for Rick and Kate.

“In order for a show to continue and to move forward, things have to change,” he said. “And things have changed, every year, for these two.”

Fillion also fielded questions about new castmate Toks Olagundoye (The Neighbors) and whether a Season 9 would have him feeling fine. Press PLAY on the video above to hear what he has to say.