An icky-sweet metaphor for codependence, ‘Together’ is romantic body horror with a heart

Michael Shanks’ “Together” is the only romance you’ll see this year that’s infatuated by John Carpenter and Plato.

A fusion of body horror and couples therapy, it centers on a sunken cave with a pool of water that, when sipped, makes cells thirst to meld with the nearest mammal. In the opening sequence, this urge to merge overtakes two dogs who smush together like the monster mutt in “The Thing.” (Thankfully, the camera doesn’t linger; the whimpering is plenty.) Now, it’s Tim and Millie’s turn. The unhappy boyfriend and girlfriend, played by real-life spouses Dave Franco and Alison Brie, have moved from the city to the forest anticipating that the scenery change will make or break their relationship. Blend is more like it.

How does ancient philosophy squeeze into a gooey metaphor for codependence? According to Jamie (Damon Herriman), a history teacher at the school where Millie works, Plato’s “Symposium” claims that humans were once rebellious, eight-limbed beings who tumbled around doing cartwheels. Zeus cleaved us pesky mortals in two as a form of control, figuring that we’d be so consumed by the quest to find our other half that we’d never get around to toppling Mount Olympus — and if that didn’t work, he’d leave us “on one leg, hopping.” (Shanks can save that for the sequel.)

It’s worth noting that Plato was kidding, a three-millennium-old joke that’s essentially, “Take my wife — Zeus!” But mating does preoccupy our mental bandwidth, and welding together two lives is unwieldy. Tim and Millie have been dating for a decade, from their hopeful 20s to their resigned 30s, and have become so mismatched in maturity that their efforts to stick together feel less like giddy Grecian handsprings and more like a three-legged race. As Millie confesses early on, “I’m not sure if we love each other or if we’re just used to each other.”

Brie and Franco lend the fictional couple their intimacy, but dial down their spark. Only a few scenes allow their characters any welcome emotional connection. There’s no sense of peeking behind their celebrity curtain, so we’re with Millie’s best friend Cath (Mia Morrissey) when she openly wishes the pair would split for good. But Millie and Tim have leaned on each other so long that neither is sure how to stand on their own. The emotional and physical pain to come has the sense of being aboard a train chugging toward certain disaster. There’s opportunities to jump off, but no one has the nerve to try.

Alison Brie, left, and Dave Franco in “Together.”

(Ben King / Neon)

Shanks is attuned to how a long-term twosome divides up duties (and identities), defining themselves by what each one contributes and, in the process, becoming less of a whole person. Tim can’t drive. Millie can’t cook. Tim is the broke musician. Millie has the steady job. “I’m the boring one,” she says begrudgingly. Meanwhile, the resentful girl struggles to label Tim’s role, stammering to Jamie that she lives with, “my partner, my Tim, my boy-partner Tim.”

“Boy-partner” sounds right. The design teams have outfitted Franco’s hipster with goofy sweatshirts and a fledgling mullet. He can’t even commit to the most famously noncommittal hairstyle. Yet, before long, Tim finds he’s unable to leave Millie’s side for a moment. Every time he touches her, the rest of the world seems to disappear: The focus goes shallow, the fine hairs on Brie’s skin dapple in the light, her muscles creak as loudly as tectonic plates. She’s confused. He keeps apologizing, becoming increasingly flustered and frantic.

The film will go on to have memorably fleshy visuals. (Picture massaging butter underneath the raw skin of a Thanksgiving turkey.) “It Happened One Night’s” Claudette Colbert and Clark Gable relied on a flimsy Wall of Jericho to keep themselves separated. Here, when things get tricky, Millie and Tim reach for an electric handsaw.

Gross? Totally. But empathetic too. Brie’s Millie is sensible and vulnerable, while Franco manages to makes us pity his bad boyfriend Tim. Part of his aloofness comes from grieving his father’s death and his mother’s subsequent mental breakdown; the rest is his shame that his rock ‘n’ roll dreams have yet to become reality. “I thought you’d make Millie cooler,” her younger brother Luke (Jack Kenny) says. “Instead …” Luke adds with a snort, as the rest of the sentence slides into the abyss, taking Tim’s ego with it.

For a first-time feature director, Shanks expertly fuses himself to the audience’s POV. He knows that we know where this is going — the title gives the game away — so his job is to goose the inevitable in ways that make us squirm and gasp. Working with the cinematographer Germain McMicking and the production designer Nicholas Dare, he plunks us into standard jump scare scenarios — the dark hallway, the subterranean lair — and then tricks our eyes into looking at the wrong corner of the frame.

His talent for misdirection also applies to the narrative. Shanks expects us to clock the unacknowledged wedding ring on Herriman’s Jamie, a Hallmark rom-com charmer, and so his script takes our suspicions and twists them once, twice and a third time for good measure. Even steeled for a plot point we’re dreading — the couple making the terrible choice to do something more adult than hold hands — when the scene finally arrives, it’s ickier and more humiliating than we could have imagined.

My quibbles with the ending are too close to spoilers to cite outright. But the delight of the film is that its editor Sean Lahiff has the rhythm of a shock comic. He favors nasty jolts and cartoonish rim shots, like when Millie advises Tim not to do anything stupid and Lahiff immediately smash-cuts to the guy running off full-tilt. Nothing about “Together” screams comedy, yet that’s precisely how it’s put together. Awkward humor is the skeleton under its prestige nightmare surface, even as it’s wonderfully, heartbreakingly tragic to watch our leads roil to melt together like mozzarella. How’s that for an update on the old quip? Make my wife — cheese!