In what is surely a sign of the actual apocalypse, Supernatural is officially coming to an end after Season 15 next year.

Jensen Ackles, Jared Padalecki, and Misha Collins shared the news with fans via Twitter today, saying, "Even though we are excited about going into our 15th season, it will be our last. Fifteen years of a show that has certainly changed my life. I know it's changed these two guys' [lives]. We just wanted you to hear it from us. Though we're excited about next year, it will be the finale, the big grand finale of an institution."

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The actors each tweeted their own farewell to the fans, but they weren't the only stars to chime in on the news. Naturally, when you've been on the show for 15 years, you've hosted a huge slew of talented guests, and Hollywood turned up to mourn the end of the beloved series that so many actors and actresses got to star on over the years.

"One of my most favorite experiences in front of the camera was getting to kick it with The Winchesters many moons ago. @jarpad @JensenAckles you will be missed!" Sterling K. Brown, who guest-starred on the show in Season 2, tweeted.

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Jim Beaver, who plays the beloved Bobby Singer, had a hilarious reaction, tweeting, "News of the day: Supernatural is ending at the end of its next season (#15) and the Mueller report was turned in to the Attorney General. Guess which story got my kid's biggest reaction. (Hint: It's the story with REAL demons.)"

Here's a sampling of the outpouring on Twitter and Instagram:


Supernatural airs Thursdays at 8/7c on The CW.

(Disclosure: TV Guide is owned by CBS Interactive, a division of CBS Corporation.)