The Lost Paradise.

Unknown to Reuben Warren, the foreman of an ironworks, his invention, the volta-dynamo, was stolen years earlier by his employer, Knowlton, and is the foundation for the iron magnate's financial empire. Reuben is in love with Knowlton's daughter Margaret, who is engaged to Ralph Standish, the son of Reuben's deceased mentor. A strike against inhumane working conditions at the mill coincides with the discovery of Knowlton's theft by Reuben, who confronts the employer with proof of his treachery. Margaret later breaks her engagement to Ralph and proclaims her love for Reuben. As Margaret's husband, Reuben now owns half of the mill and gladly meets the strikers' demands. -From TCM.com Database, powered by the AFI.