The principal cast included KJ Apa, Lili Reinhart, Camila Mendes, Cole Sprouse, Madelaine Petsch, Mädchen Amick, Mark Consuelos, Casey Cott, Charles Melton and Vanessa Morgan returning from the previous season.

The season begins with the last days of Archie, Betty, Veronica, Jughead and the rest of the gang on Riverdale High; and as they prepare for their graduation, they try to solve the mystery of 'The Auteur', the mysterious person that has been sending disturbing videotapes to every citizen doorstep of Riverdale, while also dealing with some goodbyes, break-ups and their future life on college.

Starting from the fourth episode of the season, there is a seven-year time jump, where the gang returns to Riverdale as young adults to escape their troubled pasts and also to save the town from being dissolved by Hiram Lodge.

Jones, Charles Melton as Reggie Mantle, Vanessa Morgan as Toni Topaz and Mädchen Amick as Alice Cooper, all returned from the previous season, while Drew Ray Tanner who played Fangs Fogarty was promoted to series regular after having made recurring appearances through seasons 2-4.

[37][28] He comment on his exit to be because he got "creatively bored", adding "I’m incredibly grateful for the friendships I’ve made on Riverdale, and I will miss seeing everyone on a daily basis, I’m proud to have been part of such a talented group of people, in front of the camera and behind.

[41] By mid-July, Warner Bros. Television hoped to resume the productions of its shows, including Riverdale, at the end of August.

[49] Reinhart felt that the quarantine gave her time for herself that she "already needed," while returning to filming said "I genuinely feel like a prisoner, going back to work, because I cannot leave Canada," she expressed.

[50] Apa revealed through a video on Instagram that one of the protocols of filming during the pandemic was to rinse his mouths for 30 seconds before each make-out scene, which he described as "our new normal.

"[51] In July 2020, showrunner Aguirre-Sacasa stated that there were plans for a crossover between Riverdale and Chilling Adventures of Sabrina (both of which were set in the same universe), to take place in part 5 (season 3) of Sabrina, however, on July 8, 2020 the series was cancelled by Netflix after 2 seasons due to the COVID-19 Pandemic, making Part 4 the final of the show.

[52] Zane Holtz reprised his role as KO Kelly from Riverdale's spin-off Katy Keene, following the show's cancellation after its first season.

[54][56] She captioned the note with “I’m not being Quite anymore #BlackLivesMatter.” while claiming to be the least paid actor being at the time of the tweet the only black member of the main cast.

So no need to attack them, they don’t call the shots & I know they have my back.”[54] On June 4, 2020, showrunner Roberto Aguirre-Sacasa responded to the allegations of Morgan, saying "We hear Vanessa.

In the writers’ room.”[58][59] On June 28, 2020, Bernadette Beck, who played the recurring character of Peaches 'N Cream on seasons 3 and 4, said she believed she was cast to "fulfill a diversity quota.

The second half of the season was at first schedule to premiere on July 7, 2021,[73] however, on April 29 it was announced the date was pushed back to August 11.