The beats: "Patti Cake$"

As a song cannily layered in just after its opening credits suggests, this year's Sundance sensation Patti Cake$ is, on some level, an appropriation of the Springsteen story: young New Jerseyan uses music to float themselves over the river into the world beyond. The very 21st century spin writer-director Geremy Jasper puts on it is to make this story about a girl, and one who would rather be a Missy or Queen Latifah than she would The Boss. The title is the stage name of one Patricia Dombrowski (Danielle Macdonald), a zaftig late teen living at home with a hard-drinking mother (Bridget Everett) and an ailing grandmother (Cathy Moriarty), and working two service jobs in a bid to alleviate the family debts; in her rare afternoons and nights off, she makes up rhymes with best pal Jheri (Siddharth Dhananjay), a pharmacy assistant who sees himself as the next Sean Paul, and dreams of a life apparently some distance beyond her reach. We're here to watch this young woman pay her dues, in other words, hoping against hope she may eventually earn that dollar sign at the end of her nom de guerre.

Jasper, a New Jersey native who's directed promos for the likes of Selena Gomez, evidently knows both these worlds - where his heroine's coming from, and where she aspires to be - shifting freely between Patti's fantasies and a blue-collar realism familiar from Curtis Hanson's Eminem vehicle 8 Mile. The slamdowns here come as offshoots of a macho culture, situating us deep in Soprano-land: pin-ups on dartboards, women rated as pieces of ass, kisses met with headbutts. Yet Jasper's is a comic sensibility, and he keeps undercutting his characters' aspirations in gentler, funnier ways than this life ever seems to. Walking to work, Patti daydreams of ascending to the musical pantheon, only to be jolted back to reality by a car beeping at her for straying into the road; a rare moment of connection, set to Heart's "These Dreams" - the moment Patti realises her mother once had similar hopes of escaping this town, and the moment Jasper proves he really does understand the power of pop music - is interrupted by a cut to our gal holding mom's hair back as she throws up some free shots. It is, as ever, a long way to the top if you want to rock 'n' roll.

The good news is that Patti Cake$ has a lot of fun getting us (some of the way) there. Presumably one of the reasons Fox swept in for international distribution rights is that the film's musical-triumph-over-adversity arc falls close to the contours of an established crowdpleaser like School of Rock. Yet the choices Jasper makes on a scene-by-scene basis venture substantially further out. For one thing, Patti and Jheri cut their first disc in a hut adjacent to a cemetery occupied by an amateur Satanist (Mamoudou Athie), with Patti's nan wheeled in to wheeze out some backing vocals; the group's big live break follows at an off-route stripjoint operating under the name Cheeters. These are the highs: the lows, come the second half, are properly low, such that you may start to doubt whether anybody on screen will be dropping a mic in victory at any point. Defeat and despair look to be the defaults in this harsh environment; here is a comedy that runs surprisingly close to depression, in both its mental and economic senses, which may explain why early audiences have clutched the film so closely to their hearts. (Again: we're very much in Springsteen territory.)

What keeps everybody going until the finale - in which, rest assured, music solves a lot of (if not all) problems, most touchingly the seemingly unbridgeable gap between mother and child - is the spirit of its heroine: Macdonald, in a breakthrough performance, positions Patti as a paler Precious, pissed off when she needs to be, yet finally too big of heart to fold or fail. This has been a summer in which American cinema - never more out of touch with its audience, as this year's dire box-office returns have demonstrated - has effectively thrown up its hands, tossing out a Baywatch one week, a Beguiled the next, in the desperate hope something, anything will please us. Yet there have been signs that more adventurous souls on the industry's fringes - Soderbergh with Logan Lucky, Jasper here, Sean Baker in the upcoming The Florida Project - have realised there are benefits to be gained from heading out into the country and reconnecting their art with people, as the cinema forever must. Patti Cake$ is daffy and goofy in doing this, but crucially never sneery: by the close, our heroine hasn't quite arrived on the VMA red carpet, but she has been heard out and invested with renewed hope. In 2017, we could all do with a little more of that.

Patti Cake$ is now playing in selected cinemas.