North Sea is Dead Sea (1976)

14 years old Uwe grows up in a dull multi-storey apartment building in a suburb of Hamburg. His father is an alcoholic and beats his son while he's drunk. Only together with his clique Uwe feels strong and accepted. Their aggressions focus on the Asiatic boy Dschingis. When the younger boy dares to fight back, Uwe declares war on him.