Set during the turn of the century, The Belle of Broadway starts out in Paris, where celebrated stage star Madame Adele (Edith Yorke) is making her debut in "DuBarry." During the performance, Mme. Adele's musician husband abruptly walks out of the theater, never to return. The husband takes their young son to America, where he grows into manhood. Meanwhile, Mme. Adele's career goes into sharp decline, and by 1926 she is eking out a miserable existence as a bit player. A Broadway theatrical agent who recalls the actress' glory days tells Adele that he would stage a revival of "DuBarry" in a minute -- if only Adele could recapture her lost beauty. While all this is going on, young drama student Marie Duval (Betty Compson) happens to don one of Adele's old costumes -- and her resemblance to the faded star is so striking that a scheme is hatched to pass off Marie as Adele in the newly staged "DuBarry." Soon Marie is besieged by Adele's former admirers, who can't believe that their onetime idol has retained her good looks for lo these 30 years. When one of these admirers, the Count De Parma (Armand Kaliz), makes clear his intentions to seduce Marie, the girl is saved by the timely arrival of handsome young Paul Merlin (Herbert Rawlinson) -- who, of course, turns out to be Mme. Adele's long-lost son.