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With four Oscar nominations and two wins, Daniel Day-Lewis is one of Hollywood's most esteemed and accomplished actors. The 55-year-old is all but assured a fifth nomination (and perhaps a third win) for his latest role as America's 16th President in Steven Spielberg's Lincoln.

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Now, in a newly released interview, the notoriously meticulous actor takes you inside his process and reveals that first-hand accounts helped shape his idea of this iconic figure in a profound way.

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"Reading objective accounts about the life only take you so far," he says. "What becomes more interesting to me at a certain moment is to try and grow towards a subjective understanding of that man's experience. And in that case, the legacy of his writing was hugely important. To get a sense of his thought and the movement through his thought towards a conclusion, that's a unique treasure."

Lincoln opens November 16.