What to read after Chaplin in the Sound Era?

Though Charles Chaplin is commonly remembered as a silent film comedian, it is not widely recalled that he continued to make movies long after the introduction of sound. His sound films have often been overlooked by historians, despite the fact that in these films the essential character of Chaplin more overtly asserted itself in his screen images than in his earlier silent work.
Each of Chaplin's seven sound films--City Lights (1931), Modern Times (1936), The Great Dictator (1940), Monsieur Verdoux (1947), Limelight (1952), A King in New York (1957), and A Countess from Hong Kong (1967)--is covered in a chapter-length essay here. The comedian's inspiration for the film is given, along with a narrative that describes the film and offers details on behind-the-scenes activities. There is also a full discussion of the movie's themes and contemporary critical reaction to it.