Elizabeth McGovern is perhaps best known as Countess Cora Crawley from the PBS series "Downton Abbey." Now she stars on the big screen in "The Chaperone," based on the story of flapper Louise Brooks and the middle-aged housewife who accompanies her to dance training in New York. Judy Woodruff talks to McGovern, writer Julian Fellowes and producer Rebecca Eaton about her character's evolution.