Deprived London pupils whose lives have been changed by school singing lessons are to take the stage at the British premi re of the acclaimed French feature film The Chorus.
Fifty pupils are to echo the on-screen choir during the film's end credits, and then follow the screening with an unaccompanied performance.
The choir has been assembled by the Voices Foundation, a charity which provides free in-school singing lessons for pupils and staff. Money raised from the event will go towards the Foundation's work.
Susan Digby, its founder, said: "Music can have a huge, transforming effect. You're unlocking something profound, something fundamental.
That has a knock-on effect with behaviour. Children become socially more ordered when they sing together."
The choristers have been selected from Ilderton primary in Southwark, and Oxford Gardens primary in Kensington and Chelsea, which have challenging intakes.
Since the Voices Foundation began providing singing lessons for Ilderton pupils three years ago, there have been no exclusions at the school. In November, an inspection report praised pupils for their "very positive attitudes and behaviour".
Liz Hills, the head of Ilderton primary, said: "We used to have rudeness and surliness, but their attitudes have changed now they're working together to produce something good."
The Chorus was the highest-grossing film of 2004 in France. It has since been nominated for three Bafta awards and two Oscars, including best foreign-language film.
Since its release in France last March, there has been an upsurge in membership of French choirs.
Christophe Barratier, the film's director, said: "The artistic experience can change people's lives, whether it's poetry, theatre or acting.
It's very tough to be an inspiring teacher. But I hope the film will help create some."