'Castle' cuts star Stana Katic from season 9, fans, cast revolt: Read the upset tweets

Castle fans and stars alike are not pleased after news broke on Monday that the show's star Stana Katic, who plays Detective Kate Beckett, will not be returning for the ninth season. Deadline revealed that ABC did not ask the 37-year-old Canadian actress back for the first time since the crime procedural began in 2009.

Actress Tamala Jones, who plays Beckett's bestie, Lanie Parish, was also cut from the show. Deadline also reported that star Nathan Fillion is in negotiations for the ninth season as mystery writer, Richard Castle.

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But the news that Fillion's on-screen wife and fan favorite had been ousted caused many of the show's other stars to react online.

Actress Penny Johnson Jerald, who played Captain Gates, wrote, "Waited all day to respond with dignity... NO WORDS."

Actor Jon Huertas, who plays Detective Esposito, tweeted, "To say I'm sad about @Stana_Katic & @tamalajones not coming back even if #Castle returns would be a gross understatement. #blownaway #morose. If there's a S9 of #Castle, I hope that r fans can see it fit 2 support this unknown incarnation of the show. And if I'm a part of the cast, I'll work hard 2 continue 2 keep the integrity of our show intact... #ConsiderThis #400JOBS."

Huertas went on to note that neither he nor his on-screen partner Seamus Dever (Detective Ryan) had been asked back for Season 9 yet, adding, "What else is sad???!!!! That I have to find this out online!!! This is my family! Why couldn't someone have told me #InADifferentWay?!"

Dever added, "Oh man. @StanaKatic has been a good partner and a good friend for the last eight years. Thank you, Stana. And @tamalajones is such a good actor. We haven't seen 1/10th of what she can do. Can't wait to see what role she does next."

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For her part, Jones live-tweeted Monday night's episode of Castle after thanking her fans for their years of support.

"I just wanted to thank you all @ABCNetwork, Cast & Crew & Castle Fandom.. It's been an amazing ride! Family is what we are & I love u all!!!"

Neither Katic nor Fillion has commented on the biggest cast shakeup though, leaving #Caskett fans to wonder how the show will survive without its central couple.

Castle creators and real-life spouses Andrew Marlowe and Terri Edda Miller, who stepped down as showrunners last year, also expressed their shock on Twitter.

Marlowe wrote, "Heartbroken. There are no words. #nmc."