There’s no such thing as an original musical any more, not really. Even the freshest and most exciting idea is inevitably adulterated with the vital ingredients guaranteed to bring in the High School Musical and Glee-loving crowd – most recently Rock of Ages, which went from intelligent and engaging stage show to anodyne screen romance in less time than it takes to say “Alec Baldwin looks awful in a wig”. Surely the same couldn’t be done with a film starring legendary musician/actresses Dolly Parton and Queen Latifah, though?

Oh, turns out it can.

Times is hard in Pacashau, GA. Unemployment’s on the rise, and as shop after shop puts up its shutters the beleaguered townsfolk have just one source of comfort – the choir of Sacred Divinity Church, led by choirmaster and generous church benefactor Bernard Sparrow (Kris Kristofferson). But when Bernie’s heart gives out in the middle of a service, someone has to be found to take over – and much to the indignation of his widow G.G. (Parton), it isn’t her. Pastor Dale (Courtney B. Vance) gives the job to Vi Rose Hill (Latifah), a hard-as-nails nurse and mother to obedient chorister Olivia (Palmer) and Walter (Dexter Darden), a lonely young man with Asperger’s Syndrome. Vi Rose is certainly a safe pair of hands, but does she really have the vision to transform the choir’s fortunes? Fortunately, someone who does is about to roll into town…

Just when the plot really needs a twist, GG’s grandson Randy (Jordan) pitches up at his grandma’s house. He’s very taken with Olivia, but soon realises that the only way he’ll get past Vi Rose is by seeing her at choir practice. Randy proves very popular (particularly with Olivia, whose propensity to wiggle her arse at Randy is definitely making Jesus weep) and soon the entire choir is keen to hear more of his unconventional musical tastes. His piano lessons are even a hit with Walter, who loves music but is too scared of noise and people to join the choir. It’s not long until the annual Joyful Noise contest pits church choirs from all over the country against each other; Randy might just have the ideas to take Pacashau Sacred Divinity all the way to L.A. and the national final, but if the pious and controlling Vi Rose can’t be placated then the choir’s doomed to failure. Also, there’s this bit where a really fat girl shags a spindly Chinese guy and he dies.

If you enjoyed the way that that paragraph suddenly veered off into an irrelevant and probably-going-to-irritate-Christians coda, you’re going to bloody love Joyful Noise. The plot appears to be actively constructed in such a way as to alienate any possible audience – fans of wordplay will love Queen Latifah’s sparring with Dolly (“I AM who I AM!” “Maybe you was, five procedures ago…” “God didn’t make plastic surgeons so they could STARVE!”) but wince at the saccharine follow-your-dream bullshit which permeates every scene, earnest believers on the lookout for a family-friendly film will dig the revamped heaven-heavy lyrics (“Now my God and I are the best of homies” – seriously?) but hate the thoroughly unnecessary romantic elements, and Chris Brown fans will enjoy the use of his song ‘Forever’ but deplore the absence of wife-beating.

Here’s the problem, then. Joyful Noise has a truly senseless plot, cribbed from Sister Act and Glee in equal measure. The script has its moments but it’s largely low-effort nonsense, with the occasional sharp line just serving to show up the rest. Jeremy Jordan, who is presumably supposed to be a teenager, is very obviously in his late twenties. The aforementioned fat girl breaks down at her lover’s funeral because, as she loudly explains to the pastor, she’s afraid she’ll become known as ‘Tap it and die’ (“I hear that”, murmurs the minister with a frankly inadequate level of concern), and there’s a whole subplot about Vi Rose’s husband that I simply can’t be bothered to explain. Dolly mugs and squints away, her taut, reconstructed letterbox of a mouth constrained to smiles and squeaks, and Queen Latifah growls and bellows like Marcellus Wallace post-Propecia and HRT – they’re both great, but virtually nobody else makes it past ‘average’ and not even these two ladies can be a whole film on their own. So why did I sort-of enjoy it?

Why did I leave Joyful Noise with a smile on my lips and a song in my heart? Because the music is wonderful. A variety of gospel classics, jazz and soul standards, modern pop songs and original compositions by Dolly herself are blended to stunning effect, keeping the film upbeat and watchable even when nothing else is working at all. When the credits rolled this was going to be a four-star review; by the time I got off the Tube it was down to half that. Relying on emotive music is a cheap trick which is scarily effective at hoodwinking people (gosh, I wonder why it’s so popular in churches), and director Todd Graff has done his dastardly utmost to rescue this dreadful film with a series of fantastic, well-positioned, beautifully performed songs. It’s cute, but it won’t wash. By all means buy the soundtrack – but unless you like your pleasures guiltier than Jeremy Hunt, stay out of Pacashau.