It's a Great Life plot
"Get ready for the greatest treat of your picture-going days! The great Duncan sisters in their first all-talking-singing-dancing picture!"
Sisters Casey and Babe work in a department store and every year the department store hosts a show. However, every part of the show goes wrong until Casey decides to help her sister Babe with her song. In the final act, however, the chairman sees through the deception and immediately dismisses them both. Others, however, see the potential for success and the two girls are booked for appearances on a vaudeville show. But just before their moment of glory, Babe abandons her sister and runs off with a man.