In 2004, Renaud Barret and Florent de la Tullaye ditched their respectable jobs in France and headed to Kinshasa. In the ruined capital of the Democratic Republic of Congo, a country just emerging from one of postcolonial Africa's worst conflicts, they felt strangely at home. "We were like mad dogs in a mad city," says Barret.

It didn't take them long to make friends. Barret, a former advertising agency director, and La Tullaye, a photojournalist, set about documenting the musical culture of the city's ghettos on film. "It's just crazy urban music," says Barret. "From hip-hop to funk, blues, rumba: You get many, many, many orchestras. They are rehearsing, and they've got no prospects because there's no future, but they rehearse anyway, every day."

In the course of their filming, which formed the basis of the 2007 television documentary "La Danse de Jupiter" ("Jupiter's Dance"), the duo met a group of paraplegic musicians living in the grounds of Kinshasa's zoo. Staff Benda Bilili's members had been crippled by polio, and they made their way around the city in jerry-rigged tricycles, accompanied by throngs of street children.