Emma (Julia Davis) in an episode of HBO's Sally4EverHBO

Julia Davis is a comic genius, and by genius I mean she has a profound and uncanny gift for pinpointing the horrors buried in your subconscious mind and wrenching them out into the open. Teeth flossing, those tiny brown bits you sometimes find in raw eggs, the tampon scene from Fifty Shades of Grey—all these emerge in the first episode of HBO’s Sally4Ever, visceral and depraved. And it gets worse. Gluten-sparked gastrointestinal distress. Ferrets. That moment when someone picks up an acoustic guitar at an otherwise perfectly genial dinner party. These are the kinds of nightmares that Davis is primed to exploit.

It was Davis’s macabre brilliance that brought us Camping, the dastardly British comedy about a weekend away that was adapted by Lena Dunham and Jenni Konner into a softer and substantially less funny version starring Jennifer Garner. HBO, which produced that adaptation, has imported Sally4Ever directly to American screens this time, which feels both necessary and potentially cataclysmic. I’m not certain U.S. viewers are—or will ever be—ready.

Sally4Ever is about Sally (Catherine Shepherd), a woman so meek and so diffident that she communicates most of her emotions by blinking (Shepherd, to be clear, has gifted eyelids). Sally has been in a relationship for the past decade with David (Alex Macqueen), a man whose exclusively beige wardrobe is matched in atrocity only by the noises that he makes when he moisturizes his feet. Ten minutes of Sally and David’s relationship is enough to make you want to garrote yourself with the nearest cable; that Sally has somehow survived 10 years gives a sense of how superhumanly passive she is.

That is, until she meets Emma, played by Davis. Emma is a singer and sometime actress; Emma wears jackets made of red vinyl and has never met a boundary she couldn’t obliterate; Emma is a sexual libertine who draws Sally into a profound awakening. Emma is also demented, which becomes clear the minute she shows up at Sally’s house, eye makeup streaming down her face, and somehow kicks David out, like a particularly filthy cuckoo. Graphic sex scenes ensue, both mind-bogglingly creative and extremely uncomfortable (that low boom you hear in the distance is the Family Research Council’s brain exploding).

But Sally4Ever is more than just a cringe-comedy mille-feuille. Sally and Emma represent opposite extremes: Sally has buried every impulse and desire and need she’s ever had, while Emma has unleashed her id to the point of absurdity, rejecting all notions and mores for how people—particularly women—should behave. (“So, should I pause it?” is her response after David announces during a movie that his father’s just died.) She’s a monster of self-absorption and lies, but there’s something equally monstrous about Sally’s inability to protest, or to assert herself in even the most rudimentary way.

Davis’s comedy is bleak and frequently surreal (her résumé includes stints working with Steve Coogan, Rob Brydon, and Chris Morris, whose shows Jam and Brass Eye seem to inform the tone and the fearlessness of Davis’s writing). Her use of grotesque caricatures feels raunchy in a dark and theatrical fashion, like Harold Pinter writing for Melissa McCarthy. Davis is completely unafraid to make jokes about celiac disease (a condition her father died from), colostomy bags, parental abuse, and kids on drugs (Emma is so diabolical that when she jokes that she’s given crack to a hyperactive little girl, you’re not entirely sure that she hasn’t).

The funniest moments in Sally4Ever, though, tend to be not so outrageous. They’re the way Emma pronounces “Pilates” (pill-ah-tez), and the face Sally makes watching David’s a cappella group sing George Michael’s “Faith,” and the robotic selfie stick that appears in one scene out of nowhere. They’re Emma’s attempt to rival David’s bereavement with a loss of her own (one of her friends, she weakly lies, has been “buffered by this bendy bus … just spread across the road like a stripe”). They’re the specific series of nasal exclamations David makes while dunking his tea bag. These interludes aren’t scandalizing so much as hilarious and horrifying in equal measure, just like Davis intended.

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