Earl Carroll Vanities [1945] [DVD]

Royalty from a small European principality come to New York City to arrange for a loan to prop up their country's troubled finances. While the queen mother attends to the negotiations, Princess Drina strikes up a friendship with Tex Donnelly, who owns a nightclub and gives her boogie-woogie piano lessons. When, Tex's star singer, Claire, sprains her ankle, Drina steps in and belts out a few numbers impressing Earl Carroll, a Broadway producer who had come to see Claire perform.

Danny Baldwin, Tex's collaborator, thinks that Drina is trying to push Claire out of the show, but reluctantly agrees to substitute for Claire while the singer recovers. Although Drina is engaged to the drunken Grand Duke Paul and Danny and Claire are dating one another, the princess and the night club owner realize they have romantic feelings for one another. When the Queen Mother orders Drina, for the good of her country, to immediately sever all ties with the nightclub without informing her friends, Danny and Tex are forced to put the temperamental Claire back into the lead role of the revue. ~ imdb