Archie implores Miss Grundy to share what they overheard at Sweetwater River after details of Jason's death are revealed; Betty hopes to fix her friendship with Archie, but undertakes a different tact with Veronica, who wants to make amends for her actions. Cheryl deals with the pressure of rumors about her brother's death; and tensions boil over when Jughead uncovers a secret about Archie. Meanwhile, fall pep-rally plans are scheduled to include an appearance by Josie and the Pussycats.
New information about Jason's death is uncovered and Cheryl comes under suspicion; a difficult decision leads to strain on Archie's relationship with Miss Grundy; and Betty revives the school newspaper and seeks Jughead's help in looking into the death. Meanwhile, Veronica and Ethel hear rumors of a "shame book" written by the school's football players; and, after getting grounded, Archie looks for a way out to attend an event where Josie and the Pussycats are to perform a song he cowrote.
Jughead discovers an anonymous buyer for the drive-in plans to tear it down and launches a battle to keep it open; Betty's friendship with Archie takes a hit after she uncovers shocking information about Miss Grundy's past. Meanwhile, Veronica confronts her mother about a suspicious meeting between her and a shady Southside Serpent; and after uncovering Betty's diary, Alice seizes the opportunity to destroy Archie's golden-boy image.
Archie and Veronica are shocked by the arrest but know they must come clean to their parents about what they uncovered and, still hurt by the betrayal of his friends and torn over whom to trust, a reluctant Jughead joins them in a quest for truth. Meanwhile, Cheryl confronts her mom about how she treats her as opposed to how she did Jason.
In the Season 1 finale, Archie and Veronica continue to grow closer, while Betty tires of her family acting as if nothing has happened and confronts her mother. Jughead lands in an unexpected situation, leaving Archie and the gang scrambling; Hermione makes Fred a too-good-to-be-true offer; and the truth about Blossom's family business is revealed leaving Cheryl to take matters into her own hands.