This is the new movie from the director of The Beat That My Heart Skipped, Jacques Audiard. From the trailers and first reviews I've read, it's gonna be dark, ugly and honestly violent in a way only French can do it. As far as I know, it's nominated to run for an Oscar.
"When it comes to hard-bitten crime cinema, Jacques Audiard has few equals in Europe, and his violent, gripping prison drama A Prophet shows him extending his range with unimpeachable command. The story of a gauche young inmate who rises through the criminal ranks to become a formidable player, A Prophet works both as hard-edged, painstaking detailed social realism and as a compelling genre entertainment." - Screen Daily
The official site of the movie: