|“||Jason would want us to move on with our lives. Which is why I've asked the School Board not to cancel the Back-to-School semi-formal. But rather, to let us use it as a way to heal, collectively, and celebrate my brother's too, too short life on this mortal coil. Thank you all.||”|
|— Cheryl during the assembly[src]|
The Semi-Formal is a back-to-school dance held annually at Riverdale High School.
There were rumours circulating that the event would be cancelled due to student Jason Blossom's death, but at his sister Cheryl Blossom's request, the school decided to proceed with it, hoping that it would allow everyone to not only collectively heal, but celebrate Jason's short life. It featured a performance by Josie and the Pussycats, covering Cyndi Lauper's "All Through the Night" at Cheryl's request, in honor of her brother.
Unable to summon the courage to ask Archie herself, Betty convinced Archie to attend the dance with both herself and Veronica Lodge, as she was new in town. Veronica attempted to use the opportunity to allow Betty to declare her love for Archie, so she danced with Kevin. As Betty and Archie started to dance, Archie interrupted and walked away to beg music teacher Ms. Grundy, with whom he had been having a secret affair with, to tutor him once more, and reiterated his promise to stay silent about the gunshot they had both heard the morning of July 4th. Successful, Archie then returned to Betty who had finally worked up the courage to confess her feelings to Archie, encouraged by Veronica and Kevin. She asked him if there was a chance they could ever go on to become a couple, unfortunately, Archie could not see such a future for them. Cheryl conspired to worsen the situation at her after-party later that night as she was in the mood for chaos.
Not everyone left the party in a state of despair. Kevin headed to the river for a liaison with closeted jock, Moose Mason, but their revelry ground to a halt when they stumbled upon a horrifying sight: Jason Blossom's washed up corpse, complete with bullet hole in his head.