I lived in Berlin at the time the story is set and know that district, and while there is some truth to the story (which has gotten a lot worse), I gotta say it's far fetched and overblown. Berlin is not Paris and Neukölln is not Nanterre - that area is 25 minutes by subway to city center. A far cry from growing up in da hood classics like "Fresh" (1994), this is a series of bro stereotypes: meek German teenager constantly pressured by dysfunctional relatives, immature peers and bloodthirsty Muslims. I'm from the Balkans and even I think that's a tad simplistic. The director comes from a privileged background and has an annoying preachy tendency. The film is to be used as learning material on toxic masculinity in high schools, that gives you an idea what to expect. That being said, it's well made and the acting is very good for a German film. And the pressing motive has meanwhile become very real: German youngsters (and men) feel emasculated and worthless among migrant alpha males.
Review of Sun and Concrete
