Sumas y restas (2004)
Sumas y Restas is a 2004 Colombian drama film written and directed by Víctor Gaviria. The plot follows a young real estate developer who ventures into cocaine trafficking lured by the opportunity of making money fast, but his life descends in a spiral of drugs and violence. As he did in his previous films, Víctor Gaviria opted to cast non professional actors.
More at Wikipedia.