They showed their disbelief and anger on Twitter.
The TV series was a hit with fans for not only being hilarious, but for tackling important topics such as racial profiling, sexuality and gun violence in the US. Brooklyn Nine-Nine was also the second longest running TV show on Fox, behind New Girl.
The show stars Andy Samberg, Andre Braugher, Melissa Fumero, Stephanie Beatriz, Chelsea Peretti, Joe Lo Truglio, Terry Crews, Dirk Blocker, and Joel McKinnon Miller, many of whom expressed their hope on Twitter the series would not be cancelled after all.
In addition to fan outrage, celebrities like Lin-Manuel Miranda, Seth Meyers, Mark Hamill and Sean Astin, just to name a few, added their anger online about the show's unexpected cancellation.
But there's hope: Hulu and TV station TBS have expressed interest in picking up the show, according to Deadline.
Hopefully, Hulu will save Brooklyn Nine-Nine like it did with another fan-favorite previously canceled by Fox, The Mindy Project.
Neither Fox nor Hulu immediately responded to a request for a comment.
An episode about Brooklyn Nine-Nine's characters Jake and Amy's wedding will close out the show as the series finale, airing May 20 on Fox in the US and on Netflix in Australia.
Until then, check out the cast, fan and celeb reactions below.
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