Joss Whedon's popular teen television drama Buffy the Vampire Slayer often cite Season 6, Episode 7 ("Once More, with Feeling")—in which a demon casts a spell on the town of Sunnydale that compels people to break into song—as evidence of the show's innovation and aesthetic complexity. We here at P&PC aren't gonna pick a fight and disagree with the conventional wisdom of Buffy Studies, but we do think it's worth checking out Season 5, Episode 18 of Bewitched—aired more than thirty years earlier, on January 30, 1969—as a possible precedent if not source of inspiration for Whedon's November 6, 2001 production.
Sol Saks (see the videos below), Samantha the witch comes down with a virus that makes her speak in nothing but rhyme. Initially misdiagnosed as Venetian Verbal Virus but later identified as Primary Vocabularyitis and mainly presenting in the form of couplets, her rhyming speech causes problems especially at a business dinner where her husband, an ad man, is trying to convince a dog-food manufacturer to adopt a new, more modern campaign that—get this—does not use jingles. We're not going to play spoiler and ruin the episode for you, but, as you watch, it's worth keeping in mind how "Samantha the Bard" not only links poetry with outmoded forms of communication but with disease as well. (And then, if you're taken by the logic of this convergence, go check out Dino Franco Felluga's 2005 book The Perversity of Poetry: Romantic Ideology and the Popular Male Poet of Genius, which explores the links between poetry and sickness in nineteenth-century British poetry.)