Fifteen-year-old Katri Walenska jumps a Polish ship, swims ashore and enters New York illegally. The United States Immigration officials are alerted---the USA still had a functioning immigration policy and department when this was filmed---and the search is on. Katri's only possessions are a ten-dollar bill and a letter to her parents' old friend, Jan Poldi, a former Metropolitan Opera star. She finds him in a shabby Greenwich Village apartment. His neighbors in the apartment house are three Broadway hopefuls; pop singer Terry Brennan, hoofer Buddy Fraser and Homer Tirdell and his talented dog Red Dust. (Pardon me, make that four Broadway hopefuls counting the dog.) When Terry hears Katri's magnificent singing voice, she scurries around New York to get her an audition and succeeds in getting her a spot on Don Wilson's televised amateur hour. She wins the contest but unwittingly reveals her true identity as an illegal alien, which causes the arrest of Poldi, Wilson and Dave, Terry's lawyer boyfriend. Katri faces deportation.