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.