Watch Free Online HD Moviesjoy. This expository film shows the mood of European society on the eve of the Second World War while promoting the values of international cooperation. Using the Swiss office of the BBC as an example, the film describes the functioning of radio and presents the possibilities opened by mass communications. After the advent of sound film, Cavalcanti promoted experimentation with sound, and in this connection he was interested in the communicational, organizational, and social aspects of radio.