Writer Mike White and director Miguel Arteta have quietly become one of the most effective yet underrated double acts working in independent film. They’ve created a string of nuanced, darkly funny, usually female-centric films and even one TV show, starting in 2000 with uncomfortable stalker comedy Chuck & Buck. Since then they’ve given Jennifer Aniston her best role to date in The Good Girl, gifted us with the criminally short-lived Laura Dern HBO show Enlightened, and most recently delivered Beatriz at Dinner, one of the sharpest films to tackle the current fractured state of the US.

But for their most recent projects they’ve parted ways. Last year, White wrote and directed Ben Stiller in patchy midlife crisis study Brad’s Status, and now Arteta directs and co-writes Duck Butter, a film that “comes from a very personal place” for him and his collaborator Alia Shawkat. If you need to know what duck butter means, don’t say I didn’t warn you.

As the film starts out, we’re almost in mockumentary territory with Shawkat playing an actor living in Hollywood working on the set of a film surrounded by recognizable figures playing themselves. But as Naima, she’s a far less established face in the industry, trying to impress in a small role in a Duplass brothers indie. Her desire to control proves problematic on her first day and she ends up drowning her sorrows alongside friend Ellen (Mae Whitman) at a local bar that night. When the women around her couple up, Naima becomes intrigued by offbeat stage performer Sergio (Laia Costa) and the two end up dancing.

As their initial attraction moves beyond the bar and back to Sergio’s house, a plan is concocted, one driven by frustrations felt during previous relationships. What if they pressed fast-forward and experienced the ups and downs of it all in just 24 hours, without sleep, and with sex on the hour? Naima is reticent but after she’s fired from her film she returns, eager to take a chance.

Despite a recent boom in LGBT cinema, there’s been a curious absence of films centred around the ‘L’, with most same-sex romance existing for just the one sex. Arteta’s film, if nothing else, is a proudly undiluted entry in the underpopulated world of lesbian film that, together with Sebastian Lelio’s Disobedience, literary romance Vita and Virginia, and Desiree Akhavan’s Sundance hit The Miseducation of Cameron Post, makes 2018 something of a boom year.

But while Duck Butter does help to benefit an underserved audience, it’s a film that proves difficult to fall for, despite its heady theme of intense romance. It’s essentially a chamber piece that takes place mainly in Sergio’s house, with just the two leads on screen. And while Shawkat’s nervy, controlling actor feels messily real, there’s something a bit too Manic Pixie Dream Girl about the object of her affection. The dynamic of a neurotic finding their life transformed by a free spirit is Romantic Comedy 101, and in order to sell such a connection, the latter often treads a fine line between fascinatingly magnetic and annoyingly affected.

Costa, whose striking face dominated 2015’s technically audacious thriller Victoria, is a compelling presence, but her character is so exhaustingly over-mannered it’s hard to see why anyone would see the appeal of spending 24 hours with her. The gimmick of a couple trying to condense a relationship into a day is intriguing, and speaks to a dating landscape dominated by people who are easily distracted and romantically tentative, but it becomes incredibly difficult to genuinely care about the micro-dramas that the pair encounter. Watching a couple bicker about the specifics of their relationship can be illuminating when done right, but here it becomes a chore, the problems they encounter feeling contrived and silly. After their seemingly endless day together, it’s hard to feel invested in what might happen to them next, despite committed performances from Shawkat and Costa.

It’s daring – and it really shouldn’t be in 2018 – to see a film so comfortably uncensored in its portrayal of lesbian sex and the female body, and there’s something unglamorous about how it’s shot, never edging into male fantasy territory. But there’s just so much of it, so much sex that it ultimately has a numbing effect, like a lo-fi entry in the Fifty Shades franchise.

As Brad’s Status suffered without Arteta’s confident visual eye, Duck Butter is sorely missing White’s sharp characterization. One hopes they find their way back to each other soon.