Supernatural: 10 Best Characters Who Only Appeared In One Episode

In its fictional world, the events of Supernatural are based on a poorly-performing book series written by Carver Edlund, aka Chuck Shurley, aka God.

Appearing in the Season 10 episode Fan Fiction, Marie is a high school student disappointed with the official ending of the Supernatural books. Like many a dissatisfied fan before, Marie decides to create her own alternate ending with Supernatural: The Musical.

Marie bites off more than she can chew, however, when her play attracts Calliope, Goddess of Epic Poetry. This daughter of Zeus and Mnemosyne inspires creatives, then devours them once their project is completed. When Marie’s drama teacher tries to get the play cancelled, Calliope, who had possessed a scarecrow being used as a prop, kidnaps her. Calliope kidnaps anyone who tries messing with Marie's play.

This slew of kidnappings attracts the attention of the Winchesters. Dean kills Calliope and gets to interact with Marie, who refuses to accept him as the real Dean Winchester from the books. When he tells her of the real ending which he has access to, she laughs it off as terrible fanfiction.