ABC’s ‘Castle’ season 8 spoilers: Summer Glau latest ‘Firefly’ alum to guest star

Castle -Great news for all of those who love “Firefly”: Summer Glau is finally coming to “Castle“!

As first confirmed by TVLine, the actress (whose role of River Tan remains a fan favorite so many years removed) is going to be appearing in the upcoming 14th episode of season 8 as a rival private investigator to Nathan Fillion’s Richard Castle, and the two will go toe-to-toe on a case. This should make for a pretty fun episode of the show, especially since Glau has shown some comedic chops over the years on a few separate shows. Since “Firefly” she has appeared on “The 4400,” “Chuck,” “Terminator: The Sarah Connor Chronicles,” “Alphas,” “Arrow,” and many other shows.

There’s also a nice kinship between “Firefly” and “Castle” at this point, as Glau is the third of Fillion’s former co-stars to appear here. Adam Baldwin has turned up twice now as Ethan Slaughter, and we’ve also had a chance to see Gina Torres appear in a case that was a send-up on “The Real Housewives.” We’re still not entirely sure why there hasn’t been an Alan Tudyk appearance, since he seems almost perfect for the show and Fillion worked with him on “Con Man” over the summer.

Still, we’re always glad to see Summer on a show we already watch and enjoy, and this sounds like a fun way to get Castle involved in some sort of rivalry. As for how the NYPD fits in to this episode, that remains to be seen. The show has struggled at times to figure out how to include Beckett with her new promotion in mind.

“Castle” will return to ABC with new episodes starting on Monday, February 1; be sure to head over here for some more coverage of the show! Also, sign up over here to book some other great TV news on everything we cover via our CarterMatt Newsletter. (Photo: ABC.)

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