Castle — ABC's lighthearted crime drama about a mystery novelist and the police detective who he writes about, works with and eventually marries — is undergoing a major cast change, and it has a vocal section of the show's displeased fanbase calling for its cancellation.

Stana Katic, who has played main heroine Kate Beckett since the series' debut in 2009, is leaving the show after eight seasons. "Leaving the show" may not be entirely accurate phrasing, as Deadline reported on April 18 that ABC and ABC Studios decided not to renew her contract. Adding insult to injury, the network also chose to cut fellow original cast member Tamala Jones, who played medical examiner Lanie Parish. According to Deadline's unconfirmed version of events, Katic was never even approached about a Season 9 contract and both Jones and Katic only found out they'd been cut for "budgetary reasons" in early April, as Season 8 ramps up to its finale.

Katic remained tightlipped on her exit, diplomatically telling the site when the story first broke, "Rather then distract from what was an amazing experience, I would just like to say that I’m very grateful to ABC for giving me the opportunity to be a part of a much beloved show. Thank you to the fans."

Fans were shocked at the news, given that Beckett's character is — was — 50% of the show's original premise. Despite the fact that the show is named after Fillion's character Richard Castle, Beckett is a popular character in her own right, in addition to being one half of Castle's central "Caskett" romance. Nathan Fillion's tweeted reaction, posted days after Deadline first broke the news, felt a bit tin-eared given the uproar. Writing that he wanted the show to continue for "years to come," his statement was couched in neutral, passive-voice phrases like "she will be missed" (by whom?).

And it gets messier: The same day Fillion tweeted his somewhat tepid goodbye to Stanic, US Weekly published a story alleging the two co-stars didn't speak to each other and were forced to attend couples counseling during Season 8's taping.

While Fillion and supporting player Seamus Dever have said they'll return for a Season 9, ABC has yet to reach deals with the remaining cast.Castle's fate is still unclear as of May 9, but its formerly-loyal audience's discontent has only grown louder, and #NOMORECASTLE trended nationally ahead of Monday night's episode.

Was ABC's decision a miscalculation large enough to sign the show's death warrant? Weigh in with your verdict on whether Castle should continue in the comments below.

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