Mary Barton is the pretty daughter of a factory worker who finds herself dreaming of a better life when the mill-owner's charming son, Henry, starts to court her. She rejects her childhood friend Jem's affections in the hope of marrying Henry and escaping from the hard and bitter life that is the fate of the workers, who are resentfully dependent on the callous mill-owners for their livelihoods. But when Henry is shot dead in the street Jem becomes the prime suspect and Mary finds her loyalties tested to the limit.