Watch VoirFilms. Produced for the National Federation of Building Workers Ciné-Liberté, a Popular Front organization intended to counteract capitalist interests in the film industry, Epstein’s union documentary examines building policy from the perspective of ordinary workers and notable architects. In addition to touring the Cathedral of Chartres and the Paris Exposition of 1937, the film features rare interviews with Le Corbusier (at his drawing board, no less) and Auguste Perret.