AVClub: Holiday episodes are a long-standing tradition. With so many episodes to produce in a year (especially for sitcoms), the appeal of built-in stories with clear themes makes a lot more sense. (Especially for sitcoms, which can often tie the “meaning” of a holiday to the nature of family.) Christmas episodes, Thanksgiving episodes, Halloween episodes, Valentine’s Day episodes, all clutter our DVRs for a reason—holidays structure our years the same way TV seasons occasionally do. They reliably bring up the same emotions and themes, if in slightly different permutations, and serve as instant plot engines. Still, pulling off effective, relatively universal holiday episodes is a lot harder when they’re part of a non-secular (or mainstream Christian) calendar.