George Bernard Shaw wrote the screenplay for this adaptation of his stage play, a masterpiece of social irony. Wendy Hiller is featured as Barbara, ardent Salvation Army crusader and daughter of munitions millionaire Andrew Undershaft (Robert Morely). Rex Harrison plays Adolphus Cusino, a poor classics scholar who joins the Army only to be close to Barbara. If, as the play and film adroitly demonstrate, "the greatest of our evils and the worst of our crimes is poverty," certainly the greatest of ironies is the work of Andrew Undershaft, whose munitions factory provides money for the Salvation Army, work for Adolphus, and a veritable paradise of lost souls for Barbara.