Michael Kenneth Williams has been added to the cast of Twelve Years A Slave. The actor joins Michael Fassbender, Chiwetel Ejiofor and Brad Pitt in the Steve McQueen-directed film. Raising Hope‘s Garret Dillahunt, Paul Dano and SNL’s Taran Killam are also in Twelve Years. Williams, best known for playing Chalky White on HBO’s Boardwalk Empire and Omar Little on The Wire, will play “Robert,” a mutinous slave in Twelve Years. The film is an adaptation of Solomon Northup’s 1853 book about a free black man who is drugged and dragged to the South to be sold into slavery. New Regency is backing the film. River Road and Plan B are producing. Twelve Years A Slave is filming in New Orleans. Williams is repped by The Collective and attorney Elsa Ramo.