Four "Picture Brides", from New Orleans, arrive in the Brazilian jungle on a riverboat, brought there to marry workers at Lottagrasso, a remote mining site of the Standard Diamond Mines. Also on the boat with the four "mail-order" brides (Americans Mame Smith, Flo Lane, and Gwen from England and Lena from Europe) is Mary Lee, a frightened and innocent girl, who has come to see the mine's brutal supervisor, Von Luden, about a job.
A wealthy minister in a mining town is something of an advocate for the miners' safety, but he doesn't really get involved in the issue. He is soon snapped out of that attitude, however, when his daughter is trapped underground in a mine explosion, along with the mine's owner.
Following the Spanish-American War, a soldier is given the assignment of finding the leader of a band of rebels in the Philippines. In order to do this, he must romance Roma, a cabaret spy working for the rebels. This does not please the daughter of his commanding officer, whom he is romancing.
