Redford plans to direct "The Conspirator," the story of Mary Surratt, a boardinghouse owner hanged after she was convicted of aiding Lincoln's assassin, John Wilkes Booth.
Redford's spokesman says "The Conspirator" could begin production late this year.
The film joins another high-profile Lincoln-related saga. Steven Spielberg has the film biography "Lincoln" in development, though no production date has been set.
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