THR's Actress Roundtable: Sally Field on Her Tireless Fight to Play Mary Todd Lincoln (Video)

Sally Field knew she had the facts stacked up against her, but she just had to play Mary Todd Lincoln.

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'Lincoln's' Sally Field on Becoming Mary Todd Lincoln (Video)

Though as accomplished as any actress of her generation, the 62-year old Oscar winner is just over a decade older than Daniel Day-Lewis, who plays the 16th president in Steven Spielberg's new biopic, Lincoln. And she's twenty years older than Mary Todd had been during 1865, when the film takes place. Plus, she hadn't done very many films recently -- she was now primarily a TV actress. Yet once Spielberg had mentioned that he might want her to play the part, back in 2005 before he had begun work on the film, Field was determined to make it happen.

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"Steven said 'Yes, I don't see you with Daniel, I don't think this is right, I'm sorry, I love you...'" Field recounted during a roundtable discussion with other star actresses and The Hollywood Reporter. "And I said, 'Steven, test me. I won't walk away. I won't walk away. Test me.'"

A less-than-stellar screentest seemed to have proven the director right -- until Spielberg reconsidered, thanks to some encouragement from Day-Lewis, who flew from Ireland to test with Field first hand.

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"We did some bizarre improv," Field revealed. "It was early in the process, but I became Mary, and he became Mr. Lincoln, and the most bizare improv in the history of time -- for about an hour."

And the rest, as they say, is history.

Field's comments came during THR's Actress Roundtable also featuring Oscar contenders Amy Adams, Marion Cotillard, Anne Hathaway, Naomi Watts, Rachel Weisz, and Helen Hunt. The roundtable was moderated by THR news editor Matt Belloni and executive editor Stephen Galloway.