Based on the true story of one of the most notorious crimes in FBI history, this gritty crime-thriller stars Emilia Clarke as Susan Smith, a young woman desperate to escape a seedy life of crime and drugs in a Kentucky coal-mining town. When a newly minted FBI agent named Mark Putnam (Jack Huston) recruits Susan as his informant for a high-profile case, she believes her bad luck may finally be changing. But as Susan and Putnam's relationship deepens, so does the danger, setting them both on a collision course with deadly consequences.