In Together, we witness the hideous and sacred sides of devotion, interdependence, and absolute commitment. But the crux of the film is a metaphor that is so literal, it feels like Shanks jotted the central concept on a napkin but didn’t bother to flesh out his characters or the world they inhabit. Brie and Franco strangely have little chemistry onscreen, despite their immense skill and charisma as individual actors. This might be due to their flimsy roles: Millie is a schoolteacher who wants to make a difference in kids’ lives. Tim is a jobless 35-year-old musician with a hipster mullet (one that seems to be humorously fashioned after Shanks’). Aside from a long-running dry spell in the bedroom, we’re only given the faintest impressions of their problems, of their personalities. There is little texture of a life lived together.

Together’s cast and special effects department alone could make for a substantive horror classic, but the script is freighted with distracting cliches and errant plot developments. Tim’s family trauma, while prompting some delightfully repulsive SFX, seems to exist only for that reason, or to give the film an additional whiff of dread. I believe the line, “He’s been through a lot,” was uttered more than once by Millie or one of her friends. The whole thing reminded me of the opening tragedy in Midsommar, except that event provides so much drive and necessary context for the main character. Tim’s dark family secret feels more like a gruesome invention purely for ambiance. Shanks has since explained the scene as a metaphor intended to justify Tim’s avoidance in his relationship. But onscreen it translates more as a contemporary horror trend.

Shanks’ devotion to practical effects is easily the best thing about Together, one he displays through visceral prosthetics and visual references to some of the SFX greats. In an early scene, a pair of ill-fated dogs mutate in a kennel; it’s impossible not to think of the husky sequence in John Carpenter’s The Thing, which featured pioneering effects work by industry legends Rob Bottin and Stan Winston. When Tim discovers a dying rat nesting in a light fixture, we witness a writhing, fur-covered, animatronic thing—not a glossy CGI rendering. A visual effects alum, Shanks understands that tangible phenomena often clutch at a deeper sense of fear, within the actors and ultimately the audience.

One of the most effectively frightening gags in the movie is little more than an actor in ghoulish makeup tunneling under a bedsheet. The more corporeal set pieces involving Brie and Franco are delightfully gross, and were especially taxing to shoot. (Note: unambiguous spoilers ahead.) “There were days you were stuck together for five hours,” Shanks said to Franco and Brie during the post-premiere Q&A at Sundance. “We were going to the bathroom together,” Franco interjected, a testament to the bodily intimacy demanded by the film, as well as their physical exertion.