Belle & Sebastian are one of those loveable indie-schmindie acts that, outside of the complete-works faithful, can be found nestling snugly in most record collections. Even if one finds them a little too twee after two albums, or a little samey after one, it's hard not to like the cut of their jib.

We would love to be able to say: if you see just one jukebox musical based on a Belle & Sebastian side project this year, make it God Help the Girl. We would be satisfied if we could tell you that the debut feature from singer-songwriter Stuart Murdoch isn't for everyone but fans should do well enough. Alas, neither of these things is quite the case.

Hailing from the same subset of unlovely artistic crossovers as Mr T's debut album Be Somebody or Be Somebody's Fool, the musical suffers from a shockingly tone-deaf book. Where the source album – a compilation of songs in the style of Belle & Sebastian by female singers and one Neil Hannon – was wry and sweet, the film offers only discord.

What occurs between songs scarcely qualifies as filler. The camera angles are pointedly and tiresomely eccentric and far too close. The omnipresent soft-focus glow gets very old very fast. Emily- Jane Boyle’s choreography aims for casual and ends up not caring very much. Non-sequiturs are the only consistent feature. There is nothing you could call a plot.

The characters are assigned quirks, as opposed to being written or developed. James is a dweebish aspiring singer-songwriter and unlikely lifeguard. Anton is the preening Swiss-German front-man of ill-defined punk act, Wobbly Legged Rats. Cassie is a blonde. Eve, the nominal heroine, is an anorexic, a condition that is romanticised by the opening scenes, then promptly forgotten for the rest of the film. In lieu of personality, she is creepily infantilised, all baby-doll vocal and pouts. It doesn't help that she's played by Emily Browning, a performer whose career choices (Sleeping Beauty, Sucker Punch) are underscored by Stone-Age gender relations.

Unhappily, Belle & Sebastian- brand whimsy does not translate at all onto the big screen. Murdoch’s lyrical bent (“I am the voice crying in the wilderness and she is my messiah”) sounds like fingernails on a blackboard when delivered as dialogue. Stuart Maconie’s voice on the radio provides the only evidence of life.

“Don’t Give Up the Day Job” would have been a better title.