Smashing Time (1967)

Two young women from Northern England, plain Brenda and flamboyant Yvonne, arrive in London to find fame and fortune. Misdirected and separated, they strike out on their own with Yvonne becoming a model and Brenda a waitress. After Brenda sabotages Yvonne's date--who then takes advantage of her--they lose their jobs, and soon the roles are reversed: Brenda succeeds as a model and Yvonne becomes a waitress. Competing with each other, they soon learn that they must team up to take on their adversaries in order to succeed.