Alain de Blomette, a family man, is in danger of becoming a deviant under the influence of his mistress Fanny Lacourt. He steals a bracelet, loses at gambling and contemplates suicide. His family intervenes and sends him to Equatorial Africa. Fanny, stubborn, joins him there, stirring up trouble on the plantation. The guns start talking. Alain's rival collapses and Fanny is mortally wounded. More devious than ever, Alain indulges in regrettable excesses. A fatherly inspector finally intervenes to instill in him a sense of honor.