THIS is a refreshingly inventive dark comedy. It has lots going for it: a stellar British cast (Michael Caine, Ewan McGregor, Brenda Blethyn), a script bubbling over with witty dialogue, colourful characters, poignant, bruising comedy and more than a dash of razzmatazz.

Based on the hit UK play The Rise and Fall of Little Voice, it is set in Backwater-by-the-sea somewhere in the North of England. Little Voice, or "LV", so called because she talks in a little girl's voice, is a waif-like, painfully shy, young woman who doesn't get out much. To escape her brassy, verbally abrasive mother she holes herself up in her bedroom playing old Easy Listening records from her absent father's record shop.

The house they live in is a dump. It is dangerously wired, and food is rotting in the kitchen. However, LV's mother Mari (Blethyn), fag moulded into hand and gob switched on motor pilot, has other things on her mind. After a night with second rate showbiz promotor and "loveable twat", Ray Say (Caine) she's "a woman in lust". Ray Say is the ultimate in showy tackiness, with his big red motor (personalised number plates, of course), medallion and fat cigars. Yet, this being Michael Caine, the playboy is also something of a smoothie as well.

Against all odds, romance also blooms in LV's life. When deeply shy telecoms engineer and pigeon racer, Billy (McGregor) comes to fix the telephone, the two somehow connect in the long, awkward silences between them. Billy makes some absurd advances, which in a roundabout way have the desired effect.

The story rolls along nicely as we get to know the characters. In many ways, the subject matter and tempo is similar to Mark Herman's previous feature, also set in the North of England, Brassed Off. Only here the characters are painted in broader brush strokes. One relationship is loud, raucous and crude, while the other is the antithesis: monosyllabic, coy and precious.

Events take a turn when Ray Say discovers, by chance, that LV has a special talent for mimicry. LV has spent so long listening to her records she can do Music Hall greats like Monroe, Bassy and Garland to a tee. Blown away by his discovery he sets about doing all he can to put this potential goldmine on the stage.

Little Voice is an unusual story, but an entertaining one, full of witty verbiage and close-to-the-bone humour. The actors catapault themselves into their roles. Brenda Blethyn, who was brilliant in Secrets and Lies, gives a powerhouse performance as the outrageously ballsy Mari, spewing out a stream of barbed one-liners on the one hand, yet revealing a deeper vulnerable self on the other. Caine is on excellent form too, embuing shadow and light into his loveable rogue role. McGregor doesn't have to do too much. As for Jane Horrocks, when LV gets into her stride, she sweeps you away. Horrocks, who originally played LV in the stage play, apparently does her many impersonations without the help of techno trickery, in which case her voice control is seriously impressive. This Little Voice is bound to be heard far and wide.