Once a Browncoat, always a Browncoat...

On Sunday afternoon during a virtual Comic-Con panel, Nathan Fillion welcomed a few of his former Firefly co-conspirators, including creator Joss Whedon and stars Gina Torres and Alan Tudyk. The conversation, hosted by The Rookie creator Alexi Hawley, was meant to be a reflection on Fillion's career, but it turned into a broader celebration of all the guests on the panel, which also included Fillion's former Castle stars Seamus Dever and Jon Huertas and The Rookie costar Mekia Cox.

Fillion currently stars on ABC's The Rookie and shared some memories from this past season, which welcomed Huertas, Dever, and Tudyk as guest stars for fun mini-reunions. While chatting with Torres, he also put her on the spot, asking if she'd come guest star on The Rookie, which has been picked up for a third season.

"Yes, I would. Absolutely," Torres replied, before adding a caveat: "You'll have to promise you'll actually be there because when I came on Castle, you bailed." Torres appeared on season 5 of Castle as a Real Housewives-esque reality star suspected of murdering one of her fellow castmates.

Hawley promised there wouldn't be a repeat of that scenario. "There's no way I'd bring you on the show and not write you into Nathan's story," he said.

Tudyk already appeared on season 2 of The Rookie as Ellroy Basso, a mild-mannered, crime-scene cleanup expert, technically known as a bioremediation specialist. He got involved with Fillion's John Nolan when a crime-scene cleanup took a dramatic turn in episode 8. Tudyk pointed out that his character didn't die and even embarked on a romance at the episode's conclusion.

Fillion jumped at the chance to welcome his friend back to the show. "We should revisit that," he said. "That event in your character's life was so transformative he became a self-defense teacher."

It sounds like Fillion won't rest until all his Firefly buds stop by Nolan's precinct.

Watch the video above for more.

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