“Castle” Season 8 ends on May 16 on ABC. The network has confirmed there is no Castle Season 9, so series stars Stana Katic and Nathan Fillion have both dished their own tribute to the cast and crew of the show, while fans are bracing themselves for the final time that they would see NYPD’s 12th Precinct Captain Catherine “Kate” Beckett and macabre writer Richard “Rick” Castle.

It was earlier reported that Stana Katic is leaving “Castle” because of ABC’s budget constraints. Tamala Jones, who plays Lanie Parrish, was also on her way out. At the time, Castle Season 9 was not exactly expected but fans of Nathan Fillion had hoped to see Rick in a new light -- as the titular character moving on presumably after the demise of his muse.

Related: ‘Castle’ Season 9 News: Stana Katic Leaving, cast members and Andrew Marlowe disappointed

That Kate Beckett dies in the “Castle” Season 8 finale was something the fans both feared and anticipated. Series creator Andrew Marlowe and his wife and co-showrunner Terri Edda Miller had planted Castle and Beckett in a solid ground before leaving the series in the hands of longtime writers Alexi Hawley and Terence Paul Winter. There is no plausible way for Beckett to leave Castle except by death.

Some fans did hope for “Castle” to be cancelled rather than going on without Stana Katic. They are posting their reactions in social media sites now, saying, “ABC heard us.”

It’s a shame that the “Castle” Season 8 finale was not exactly planned to be the series ending. The producers reportedly filmed two possible endings – Plan A in the event of a series renewal, Plan B in case of a series cancellation. A fan would guess that Beckett dies in one of those plans. And now that there is no “Castle” Season 9, the showrunners could deliver some kind of “happy ending.”

Marlowe and Miller actually did deliver a wonderful series finale type of season ender a year ago: Beckett is about to become a senator, fulfilling a prophecy delivered by a time traveler from an old episode. In case the “Castle” Season 8 finale fails to satisfy the fans, they could always go back to “Hollander’s Woods,” the seventh season finale which also has an answer on why Rick decided to become a macabre novelist.

Here are social media posts from Stana Katic and Nathan Fillion, who have both gone on Twitter to connect to fans soon after ABC’s cancellation announcement was reported.

Related: 'Castle' season 8 episode 14 spoilers: Firefly's Summer Glau is in; Castle recruited by Greatest Detective Society

Goodbye Kate Beckett – Stana Katic on Twitter

Nathan Fillion may (or may not) live tweet the final episode of “Castle” on ABC

“Castle” supporting actor Jon Huertas (Javier Esposito) also tweets farewell message(s)

Molly Quinn (Alexis Castle) also has a farewell message

And from Rick Castle’s mother, Martha Rodgers:

“Castle” Season 8, Episode 22 is titled "Crossfire." Let us know what you think of the series finale in the comments section below!