Many arts have influenced the cinema over extended periods of time. One art – radio drama – is an exception, for we can date the onset of its influence from the coming of synchronous sound to the cinema in 1926 and the culmination of it with the creation of CITIZEN KANE in 1941. Film and radio drama were thereafter to part company, each having learned what it could from the other. What had the cinema learned from radio drama? If we look closely at CITIZEN KANE, we can learn much about the virtues and limitations of radio design, cinematical design and the design of CITIZEN KANE itself.