Favela Rising, directed by Jeff Zimbalist, is set in the grim reality of the picturesque slums overlooking Rio de Janeiro. The documentary tells the story of a place, a man, a moment, a movement, and, ultimately, a miracle. The place is Vigario Geral, the worst of Rio's favelas, or slums, where barbaric drug armies battling corrupt police were the norm a decade ago, and drug dealers were the favela's only role models. The man is Anderson Sa, a Vigario native who saw his first deadly street violence at age 10. The moment is August 1993, when cops massacred 21 innocent favela residents in response to the killing of four of their own by a Vigario drug lord. The movement is AfroReggae, a nonviolent flowering of Afro-Brazilian culture through dance, theater and popular percussion-fueled reggae bands, which Sa and some of his contemporaries founded in response to the massacre. "Music is an instrument of change," says one of the AfroReggae founders. The drug lords even began to send their own kids to the AfroReggae programs. In response to the police killing of one of their own, Grupo AfroReggae made a video showing police brutality to a throbbing beat, but eventually they created a program that reached out to the cops, too, who were encouraged to form their own theater group and band. Miraculous as that seems, that's not the only miracle in this miracle of a film.