The first season focuses on the town of Riverdale in the aftermath of the death of Jason Blossom (Trevor Stines), who supposedly drowned the summer before school started.

[41] At San Diego Comic Con 2016, Aguirre-Sacasa explained that the first season would follow what happened to Jason Blossom, a teen who died the summer before school started and stated that the murder solving would not be dragged out.

[19] In March 2016, it was announced that Ross Butler, Daniel Young, and Cody Kearsley would be joining the show in recurring roles as Reggie Mantle, Dilton Doiley, and Moose Mason respectively.

[51] The score for the season, composed by Blake Neely, was released on a physical CD by La-La Land Records, and simultaneously on download by WaterTower Music, on July 18, 2017.

The site's critics consensus reads: "Riverdale offers an amusingly self-aware reimagining of its classic source material that proves eerie, odd, daring, and above all addictive.

[61] Jeff Jenson of Entertainment Weekly similarly praised the show, stating that Berlanti and Aguirre-Sacasa "built a sturdy, appealing foundation", as well as paying homage to pop culture and "[spitting] on them too.

"[62] Writing for The Washington Post, Hank Stuever commented on the show's departure from its source material, stating that it's watchable but "entertainment value comes at a steep price, cashing out Archie's underlying innocence to depict the corrupted community he calls home."

"[65] Daniel D'Addario of Time also criticized the adaptation from the source material, the voice overs by Cole Sprouse and the many cultural references the show makes.

She criticized the inclusion of the murder plot lines, stating the show "missed [an] opportunity to tell a strong, high school-set story".