On the night of 12-13 August 1961, the GDR erected a wall that separated Berlin in two. Very quickly, the cinema takes hold of the subject. In the West as in the East, spies, fugitives, smugglers, agents of the Stasi are waging a cold war that inspires writers and directors - Illustrated by numerous film extracts and punctuated by testimonials from actors and directors, film tells the crossed story of the Wall and German cinema.