The 1951 film that is about a dodgy tycoon's mistress who undergoes a "My Fair Lady" like transformation is "Born Yesterday". This movie is a comedy-drama which was directed by George Cukor. It is based on the play 'Born Yesterday' by Garson Kanin. Credit for the screenplay went to Albert Mannheimer. Garson Kanin's help was uncredited because of legal entanglements. S. Sylvan Simon is the man who successfully produced this film. Its distribution was by Columbia Pictures.

In the film "Born Yesterday", Brassy blonde moll Billie Dawn (Judy Holliday) hits Washington, D.C., with her unscrupulous millionaire sugar daddy, Harry Brock (Broderick Crawford). Brock has brought his sleazy lawyer, Jim Devery (Howard St. John). Devery has been pressuring Harry to marry Billie by pointing out that a wife cannot be forced to testify against her husband. In an effort to make Billie more socially acceptable, Harry hires newspaper journalist Paul Verrall (William Holden) to smarten her up. Sparks soon fly between Paul and Billie.

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