A certain kind of special holiday episode has long been a tradition across the pond. In the U.K., these episodes—divorced from the overarching story lines of any given series—are meant to be largely stand-alone treats that might appeal to viewers who may never have seen another episode of, say, Doctor Who or The Office. Once upon a time, American episodic TV took the holiday season off—but now, American TV is slowly starting to catch on to this festive tradition, with Netflix leading the charge by ramping up on original December programming.

The finest example of this new British/American hybrid strain is this weeks on-off episode of Chilling Adventures of Sabrina, subtitled A Midwinters Tale. Series show-runner and Archie Comics Chief Creative Officer Roberto Aguirre-Sacasa chatted with Vanity Fair about the unusual way this hour of TV came together, and the fun Easter egg and allusions waiting for fans within.

When Chilling Adventures of Sabrina first got the green light by Netflix, Aguirre-Sacasa was given a two-season order and set about shooting both back-to-back. Production was already in full swing on Season 2 when the Riverdale show-runner realized he wanted to capitalize on the long tradition of holiday ghosts and ghouls—A Christmas Carol, anyone?—in the form of a post-Season 1 holiday special. After getting the grudging go-ahead from a production staff that grumbled Aguirre-Sacasas idea was, in his words, “complicated and annoying,” the next step was to get Netflix to sign off. The streamer was far more enthusiastic about the idea, with one executive cutting off Aguirre-Sacasas pitch with an eager question: “Could this be a Christmas present for our fans?”

The result is a special that carefully straddles the line between stand-alone and serialized episode. Season 1 ended with Kiernan Shipkas goody-two-shoes Sabrina choosing the Satanic Path of Night—and, in the closing shot, seemingly going full bad girl, with freshly bleached hair and a soundtrack to match.

The trailer for next year doubles down on this promise of an edgier Sabrina, with a cover of the Runaways “Cherry Bomb” blaring over shots promising that come April 5, 2019, the teenage witch will be breaking bad . . . or at least trending more naughty than nice.

Just dont expect to see this darker brand of Sabrina in the “transitional” A Midwinters Tale—where, as Aguirre-Sacasa admits, her “hair really is the biggest thing” thats changed about her. In fact, Aguirre-Sacasa said he wasnt even sure if this episode would end up being a Christmas special or the first episode of Part 2. The cliff-hanger ending of the holiday episode indicates a Season 2 premiere set in January rather than April—so its possible that once upon a time the entire plan was to set this second installment of Sabrina deep in the dark winter. “I kind of had to thread the needle a little bit,” Aguirre-Sacasa said of an episode wherein which the evolution of several relationships is put on hold as holiday hijinks erupt all around the members of Sabrinas coven.

Here, according to Aguirre-Sacasa, the writing staff—populated, in part, by real-life pagans—had a field day digging through holiday folklore to find supernatural creatures capable of menacing the Spellman clan. In addition to Bartel (a version of the well-known Christmas demon Krampus), the episode rolls out a traditionally Icelandic witch known as Grýla and a pack of impish poltergeist-esque figures known as “The Yule Lads.”

But take a closer look at the trailer, and youll see a few non-Wiccan allusions lurking in this particular non-holiday adventure. Sabrinas attempts to contact her late mother, Diana, comes with a visual nod to the classic wedding-dress seance scene in 1988s Beetlejuice. (The ever-modest Aguirre-Sacasa said, “Beetlejuice does it brilliantly. We do it O.K.”) Theres also an allusion to a holiday oddity from the original Archie Comics, a story line in which Sabrinas friend Susie (Lachlan Watson) gets a chance to dress up as Jingles, an elf who would appear in Archies bedroom in the books every Christmas to cause mischief.

Fun film and comic-book allusions aside, Aguirre-Sacasa sees this episode as “a lovely, melancholy grace note to the first season,” one where “the last embers of the Harvey-Sabrina romance” burn just brightly enough to keep us all warm and cozy. A Midwinters Tale premieres on Netflix December 14.

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