Stephan Gregorovitch, the unwilling king of a bankrupt Ruritanian country, along with his hucksterish chancellor and musically-inclined bodyguard, travel incognito to London for some fun. An invitation to a party held by Duke Hugo seems just the ticket, but the presence of jewel thieves in the vicinity soon puts paid to any ideas of a relaxing evening!
Impoverished aristocrat's daughter Tommy Tucker is in love with radio announcer Bill Coverdale, but he is engaged to her more glamorous sister Angela, who he does not love. Seeking escape from this hopeless situation, and her life of genteel poverty, Tommy flees abroad to Biarritz to become a nightclub singer.