Hanks & Thompson on the Disney 'Zeitgeist'

What's it like to portray one of the most famous people in history? Tom Hanks channels Walt Disney opposite Emma Thompson's P.L. Travers in the charming, poignant Saving Mr. Banks, and he tells ET's Nancy O'Dell that he felt a true responsibility to portray the icon in the right light.

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"Family, world, zeitgeist, consciousness, the whole shebang," laughs Hanks about the weight of responsibility in portraying Disney properly. Watch the video for more, including what it was like to work with good friend Emma and how many times the two stars have seen Mary Poppins!

In select theaters December 13 and everywhere December 20, Saving Mr. Banks chronicles the real-life struggle and untold backstory of how the Disney classic Mary Poppins made it to the big screen. Disney's daughters begged him to make a movie out of the beloved Travers book, but when the curmudgeonly and uncompromising Travers refused to yield to Disney's magical vision, his promise to his daughters turned into a 20-year quest to obtain the rights and find a way to please Travers.

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Also starring Colin Farrell, Paul Giamatti, Jason Schwartzman, B.J. Novak, Bradley Whitford, Ruth Wilson, Melanie Paxson and Annie Rose Buckley, Saving Mr. Banks is directed by John Lee Hancock.