Rusty (Rita Hayworth) is a chorus girl at a nightclub run by her boyfriend Danny McGuire (Gene Kelly). Fellow showgirl Maurine Martin enters a contest to be on the cover of ''Vanity'' magazine, so Rusty tries out as well. When Maurine is given a lukewarm evaluation by Cornelia Jackson (Eve Arden), she sabotages Rusty's chances, giving her terrible advice on how to act toward Cornelia. Cornelia's boss, magazine editor John Coudair (Otto Kruger), decides to check out Maurine at Danny's nightclub, but his eye is immediately drawn to Rusty. It turns out that 40 years earlier, he had become instantly smitten with showgirl Maribelle Hicks, whom Rusty looks exactly like; he later discovers that Maribelle is Rusty's recently deceased grandmother.