In 1940, Sudan is still under French colonial rule. The story revolves around three individuals: Doctor Bourdet (Harry Baur), colonial commander Bréval (Victor Francen), and Lieutenant Parent (Jacques Dumesnil), Bréval's second-in-command. When Parisian tourist Danièle Mourrier (Annie Ducaux) pays a visit to the Sudan, both Bréval and Parent fall in love with her. Eventually, Bourdet discovers that Bréval has contacted leprosy, forcing the commander to remove himself from the romantic triangle. Upon Bréval's unexplained disappearance, the heartbroken Danièle marries Parent, but three years later returns to Bréval when the latter shows up again to complete a long-delayed dam project.