Rapper Boots Riley’s first feature film shows a great deal of spirit and promise, and further secures Lakeith Stanfield as the one of the key performers of the moment. That’s my very polite way of saying I respect this movie, but wanted to like it more than I actually did. Despite being about serious matters (labor relations, systematic oppression, racial microaggressions), Sorry to Bother You is slight and raggedy, but when it leans into its surreal, midnight movie instincts it proves engaging and amusing.

Cassius Green (Stanfield, once again immediately sympathetic with just a glance) lands a crappy job at a scummy call centre. His male managers look like they haven’t bathed in months; the female one (a very funny Kate Berlant) has one of those stapled-on smiles that makes you want to leap from a building. The movie gets into gear when Cassius makes his first sales calls: his desk “drops” into the home of whomever he’s dialled-up, no matter what they are doing. He gets a tip from an older cubicle-mate played by Danny Glover: “Use your white voice.”

Cassius doesn’t just do that (and these lines are dubbed in by David Cross) but he has a knack for getting inside the heads of those he’s pitching to. Meanwhile, his co-workers, led by Steven Yeun, are preparing to unionize. Just as they lead a walkout, Cassius gets called upstairs to become a “power caller”. Will his allegiance stay with his people, or will he go after the money? The fact that his Uncle (Terry Crews) is about to lose his home (the garage of which Cassius lives in) adds a little extra herb to the soup.

Beside him through all this is his girlfriend Detroit (Tessa Thompson), a performance artist and roadside sign holder/dancer whose actually part of a band of underground culture jammers against “Worry Free”, which just so happens to be Cassius’s next client. Worry Free is an even worse deal that the one in Downsizing. With a life-long contract you get free housing and meals and a manufacturing job. The factories/dormitories are blinged-up prisons. These people are essentially slaves.

We learn about Worry Free through one of the film’s many television inserts, which is not exactly Riley’s strongest directorial play. Cassius’s world is modern-day Oakland one minute, Idiocracy the next. Instead of feeling like an exaggerated version of our world, it comes off like half-baked science fiction. This lack of cohesion is a bit disappointing, as is a very unadventurous visual style on Riley’s part.

But then there’s the comedy. Armie Hammer is marvellous as the sarong-wearing CEO of Worry Free, precisely because he doesn’t chew up the scenery. He lets the ridiculousness of his extravagant, cocaine-fuelled house party do a lot of the work for him. Tessa Thompson is also delightful in a role that could have just been the preachy, moral girlfriend. (Extra points for her recurring gag of enormous earrings that tote radical action phrases in a font you’d find on the old Electric Company television show.)

Then there’s Stanfield, slapped around by indignity at every turn and always taking it on the chin. I was similarly mixed on Come Sunday, which also debuted this Sundance, but Stanfield’s performance in that as a church organist struggling with his sexuality was a stunner.

Sorry to Bother You is miles away from the gloss of that film’s “prestige picture” vibe. This is low-budget, weird and substantially punk rock in its defiance to genre. This will definitely resonate with young people busting their hump at a miserable job, but, weirdly enough considering its pro-labor stance, it’s best served as Boots Riley’s calling card for bigger films.