In the Buffy the Vampire Slayer season 3 episode (3x06), Sunnydale’s adult population regresses into rebellious, irresponsible teenagers after eating chocolate bars sold for a high school band fundraiser. Plot Summary
Giles and Joyce bond over the song "Tales of Brave Ulysses" by Cream, a moment that fans often revisit for its emotional resonance later in the series.
As the adults consume the candy, they start acting like reckless teens. Giles reverts to his "Ripper" persona—a punkish, violent delinquent—and Joyce becomes a rebellious, flirtatious girl. Even the usually stern Principal Snyder turns into a desperate-to-be-cool nerd.
The episode is iconic for showing the chemistry between Giles and Joyce, who end up making out on a police car while in their regressed state.
It provides a rare look at Giles' dark past and humanizes Joyce beyond her role as a protective mother.
While Buffy is stressed about studying for her SATs and her mother, Joyce, and Watcher, Giles, are breathing down her neck about her schedule, the local school board begins distributing "band candy". Unbeknownst to the town, the chocolate has been cursed by Giles' old rival, , acting as a subcontractor for the vampire Mr. Trick .
If you're looking for more, I can provide a of Giles' "Ripper" persona or explain how this episode ties into the Mayor's overall plan for the season.