Morocco’s best-known international director, Nabil Ayouch, is currently in Marrakech lensing a stark social drama about prostitution. Since his early films, such as “Ali Zaoua: Prince of the Streets,” 45-year old Paris-born Ayouch has specialized in realistic dramas that focus on the desperate plight of underprivileged Moroccans. He has directed some of Morocco’s biggest international...