We see how the coming of sound in the 1930s upended everything. We watch the birth of new types of film: screwball comedies, gangster pictures, horror films, westerns and musicals, and discover a master of most of them, Howard Hawks. Far away from Hollywood, in England Alfred Hitchcock hits his stride and French directors become masters of mood. And we discover that three of the great films of 1939 – The Wizard of Oz, Gone with the Wind and Nintochka – have something in common.