Stephane Girard's life began to unravel with frightening speed after his partner threw him out. "I lost everything," he says, sitting in the bright, funky surroundings of homelessness charity Crisis's Skylight Cafe in east London. "I lost custody of my son and ended up sleeping rough," he says. "I was taking drugs, drinking and was depressed and violent. My life descended very quickly."
His life changed trajectory after a music tutor at the Skylight Centre persuaded him to take part in a competition the charity was holding to find hidden musical talent among London's homeless population.
The Consequences project offered an opportunity that most aspiring musicians would sell their granny for: the chance to play in front of thousands of people at the Roundhouse venue in Camden and contribute to a charity track alongside stars such as Paul Weller and Supergrass.
A series of auditions, a lot of rehearsals and a few jamming sessions later, Girard will step out on stage in little over a week's time with his fellow band members - guitarists Paul Webb and Roberto Medina, singer MaxLove and drummer Neil Thompson - and perform the charity track Consequences for the first time.
The band members, who have all struggled with homelessness and destitution, will share the stage with some of the biggest names in music. They will play one of Girard's own songs during an all-day gig on March 2 that will feature Paul Weller, Supergrass, Dirty Pretty Things, New Young Pony Club, Graham Coxon and the Noisettes.
Phil Drew, one of the project's coordinators, says that the single - due to be released in April - is loosely based on the game, consequences, where each player draws a section of a body without seeing what has been drawn before.
Without hearing one another, more than a dozen artists each played a refrain over a skeleton track, without knowing what had come before, or what would come after. The track was then built up, layer by layer, by producer Paul Epworth.
"The idea behind the Consequences project is that the future is unwritten and it can unravel in unpredictable ways," Drew says. "It aims to unlock hidden or existing talents of homeless people to help people rebuild their shattered confidence."
The campaign aims to attract a different type of donor, says Drew. "The Crisis donor demographic is often middle-class and middle-aged and although we want to guard that, we are also looking to attract young, reasonably affluent urbanites."
How can the competition help homeless people who may not have the musical talent of the Consequences band? Jane Eggleton, spokeswoman for Crisis, says the campaign aims to raise around £250,000 to help homeless people around the country.
Paul Webb, a former graphic artist who plays guitar on the Crisis track, says his self-esteem was shattered after he became homeless. "I lost a lot of confidence and it took me a long time to pluck up the courage to go into the music room," he says. "This is a big confidence boost. The single could go to number one. It's great stuff."
· Crisis Consequences Live takes place at the Roundhouse, London on March 2. Tickets available from 0870 389 1846 or from the Crisis Consquences website