Based on a four-issue comic book series, Happy! is an American adult animated black comedy television series based on a comic book of the same name written by Grant Morrison and artist Darick Robertson. This series is majorly directed by Brian Taylor.
Happy Season 3: Is It Renewed?
As informed by Syfy, they officially canceled the TV series Happy!. The reason they gave was due to lackluster ratings.

Happy Season 3: Cast Details
You will find a long list of the main characters in Happy! But the lead role is carried by Christopher Meloni as in the role of Nick Sax, who is a detective but an alcoholic also. Patton Oswalt voices for the character of Happy who is a goofy, cartoonish winged unicorn. They both are considered as protagonists. Another character, Ritchie Coster plays the role of a wealthy boss. Lili Mirojnick plays the role of a veteran detective, Medina Senghore as Amanda Hansen, Bryce Lorenzo as Hailey Hansen. Some other characters were also part of the previous seasons including Patrick Fischler, Joseph D. Reitman, etc.
Since the list is very long we are not mentioning everyone’s name. But as there is no official announcement regarding the comeback of the new season then there is no updates list of casts available for season 3. So we can expect the previous cast members in the new season.

Happy Season 3: Release Date
Season 2 of Happy! was premiered on Syfy March 27, 2019. But after this, Syfy announced for the cancellation which is really very bad news for the audience. But there is still some possibility that some other network will pick up the show and the audience will get to see their favorite series on screen. But until now there is no announcement regarding the release date of Happy! season 3.