Keri Russell and Mahershala Ali have signed on to join Matthew McConaughey and Gugu Mbatha-Raw in the Civil War drama The Free State of Jones. The plot is based on the true story of Newton Knight (Matthew McConaughey), a Southern farmer who fell in love with a slave named Rachel (Gugu Mbatha-Raw). This relationship lead him to rebel against the Confederate Army.

Actress Keri Russell is set to play Newton's wife Serena, while Mahershala Ali is portraying Moses Washington, an escaped slave who becomes Newton's ally in his fight to secede from the Confederacy. Production is already under way in Louisiana, although no other cast members have been confirmed at this time.

Gary Ross (The Hunger Games) is directing from his own screenplay and producing alongside Scott Stuber and Jon Kilik. Robert Simonds' new production venture STX Entertainment is also producing, with Route One/Union Investment Partners and Vendian Entertainment providing the financing. IM Global will handle international distribution, although a domestic distributor is not in place yet.

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Keri Russell recently starred in Dawn of the Planet of the Apes, and she can currently be seen in Season 3 of the hit FX drama series The Americans. Mahershala Ali played Boggs in last year's The Hunger Games: Mockingjay Part 1, a role he will reprise in the franchise finale The Hunger Games: Mockingjay Part 2.