These days, when Roger Ebert calls a film “funny… observant, and thought-provoking,” you’d do worse than to entertain a few other opinions before you sit down to watch it. Ebert’s not all wrong: Humpday is observant—it’s just that what it observes is pitifully banal. This is the third feature from mumblecore actress-editor-writer-director Lynn Shelton, who is well entrenched in the sub-genre, having directed two of her own films, as well as having starred in Greta Gerwig and Joe Swanberg’s middling 2008 picture Nights and Weekends.

Mark Duplass—who appears opposite Gerwig and Ben Stiller in Noah Baumbach’s mumblecore-with-a-budget Greenberg, which still has yet to be officially released here—plays a would-be hipster sliding somewhat uncomfortably into adulthood with his new wife in Seattle. An old friend of his turns up on his doorstep unannounced, and he lets him stay in their spare room until he gets settled. They end up at a house party with a bunch of free-spirited polyamorous swingers, where a sign on the front door reads “Dionysus.” (The script must’ve been written on a few paper napkins post-happy-hour at Shelton’s local bar.) Anyway, the swingers start talking about how they’re entering Humpfest, an amateur-porn film festival put on annually by the city’s alternative weekly, The Stranger. Duplass and his buddy, pretty trashed at this point, come up with a plan to make a no-budget ‘art-porn’ short film in which they, two straight men, have sex. Duplass describes it simply to his wife as ‘an art project’; she’s understandably taken aback when she finds out what he’s really planning.

The premise is relatively interesting, but the execution, and the complete lack of chemistry between any of the actors, is painful to watch; the film, intriguing at the outset, quickly fizzles. Explaining the lack of chemistry: as someone observes at the start of one of the two completely unnecessary audio commentaries, Duplass met the actress who would play his wife only half an hour before the first scene was to be shot. Mumblecore films are for the most part improvised around a skeleton script, but the text here feels much more like the makings of a mildly entertaining short film than an entire feature. What little good improvisation there is appears in the hotel room scene as the two are about to start shooting their film, but it’s squandered by poor editing and generally awful cinematography. Mumblecore films aren’t supposed to be high art, but even the worst of them are somewhat pleasant to look at—unfortunately this one isn’t. Because there’s no chemistry between the actors—it’s hard to believe, at any point in the film’s 94 minutes, that these dudes were once best buddies—the film frays into a million loose ends at about the halfway point, and never recovers.