Here’s what I think. There should be a rule in place, and that rule should state that we only have to deal with one dark comedy about a UK indie band per year. 2010’s was Killing Bono, which is all well and good if that’s your sort of thing, but what will be 2011’s? In the interests of making sure that there is still any sort of music or film industry left in Britain to produce the 2012 effort, I strongly recommend we don’t nominate Powder as this year’s official indie rock flick. Christ knows there’s no pleasure in slamming low-budget productions, but sometimes slamming is all you’re left with…

Powder tells the story of the grams (deliberate lack of caps), a Liverpool band with big dreams and even bigger problems. The sycophantic singer of their former support act stole one of their songs and turned it into an enormous hit, their frontman and songsmith is a tortured artist as drawn by a three year old on a paper napkin, and they are inexplicably being managed by Alfie Allen and his horrible puffy face.

With thieving bastard Helmet (Weaver) and his group the Transbad Saints on their way to break the States, disillusioned frontman Keva (Boyle) and his long-suffering bandmates finally land a record deal and the chance to see their names in lights. But if they’re going to cut the disc they’ve dreamed of then Keva needs to find a very old friend, face up to his demons and finish writing a song he started a long time ago. That’s a whole lot of big asks when you’ve got to spend three hours a day practicing looking moody with a fringe.

Nothing would give me greater pleasure than to think of something nice to say about Powder. Everything about it screams ‘well-intentioned little indie number’ – the director is a professional editor making the jump to the big chair for the first time, the screenplay was written by the real-life band manager on whose book it’s based, the cast are mostly bit part actors looking for a break. It’s cheap, it’s earnest and, unfortunately, it’s utterly dreadful. From the very first scene (handheld camera follows Keva as he mooches around V Festival in a mac, looking like he’s frantically searching for some hidden depths), every conceivable cliché is rolled out in seamless formation – there’s the madcap band member who wanders around in his pants, the Mockney lass who has clearly been told to act too intelligent to be a groupie (groupies aren’t meaningful enough for Keva) and the vampish rival rockstar whose affected drawl conceals a petulant and childish streak.

Liam Boyle’s central performance as Keva is bloated with self-importance, whilst the sycophants who surround him are never allowed to progress beyond the level of courtier – his music is repeatedly described with the sort of gushing purple prose normally reserved for people like Jesus, which probably worked better as a conceit when Powder was a book and its audience wasn’t treated to regular blasts of insipid rock seemingly calculated to undermine the cast’s hero-worship. Wheezer, Alfie Allen’s chippy band manager, is inexplicably loaded down with unwieldy lines that sound at least seventy years old (memorably, and all in one go: “What the heck! They’re having a blinking laugh! This is tommyrot!”), whilst Keva’s nemesis Helmet is a foppish and one-dimensional caricature drawing equally from Bertie Wooster and Grand Moff Tarkin.

The plot is lazily wrenched to accommodate a trip to Ibiza (cue some deeply gratuitous tits) and a couple of scenes that shamelessly plunder This Is Spinal Tap, but otherwise it lurches from gig to meaningful-conversation-fag-break and back again, over and over. Witless, childish and with an inexplicable whiff of Amadeus lingering around the central rivalry, it’s enough to make you wish Boyle’s monosyllabic Merseyside Salieri had just cracked on and slit his throat at birth.