Judy Holliday in Born Yesterday (1950)
Judy Holliday stars as Emma "Billie" Dawn, an ex-showgirl and mistress to crooked junkyard tycoon Harry Brock. She's young and uneducated but is out to prove that she's not as dumb as those around her make her out to be. To prime her for capital society, Brock hires Billie a tutor and she ends up flourishing under her new schooling. Her eyes are opened to not just the literary classics, but her boyfriend's foul business dealings. She leaves Brock in hopes of a new life, one where she's much more than a man's accessory.