Mabel decides to put on a sock puppet rock opera to impress a local puppeteer, but her show goes awry when Dipper's drive to uncover journal secrets leads to a supernatural disaster.

In three separate mysterious tales, Stan is cursed by a Witch, Waddles accidentally eats a bowl of brain-enhancing jelly and builds a machine that allows him to speak for the first time, and Mabel faces her fear of Claymotion.